my_pickle.py

"""Create portable serialized representations of Python objects.

See module copyreg for a mechanism for registering custom picklers.
See module pickletools source for extensive comments.

Classes:

    Pickler
    Unpickler

Functions:

    dump(object, file)
    dumps(object) -> string
    load(file) -> object
    loads(bytes) -> object

Misc variables:

    __version__
    format_version
    compatible_formats

"""

from types import FunctionType
from copyreg import dispatch_table
from copyreg import _extension_registry, _inverted_registry, _extension_cache
from itertools import islice
from functools import partial
import sys
from sys import maxsize
from struct import pack, unpack
import re
import io
import codecs
import _compat_pickle

__all__ = ["PickleError", "PicklingError", "UnpicklingError", "Pickler",
           "Unpickler", "dump", "dumps", "load", "loads"]

try:
    from _pickle import PickleBuffer
    __all__.append("PickleBuffer")
    _HAVE_PICKLE_BUFFER = True
except ImportError:
    _HAVE_PICKLE_BUFFER = False


# Shortcut for use in isinstance testing
bytes_types = (bytes, bytearray)

# These are purely informational; no code uses these.
format_version = "4.0"                  # File format version we write
compatible_formats = ["1.0",            # Original protocol 0
                      "1.1",            # Protocol 0 with INST added
                      "1.2",            # Original protocol 1
                      "1.3",            # Protocol 1 with BINFLOAT added
                      "2.0",            # Protocol 2
                      "3.0",            # Protocol 3
                      "4.0",            # Protocol 4
                      "5.0",            # Protocol 5
                      ]                 # Old format versions we can read

# This is the highest protocol number we know how to read.
HIGHEST_PROTOCOL = 5

# The protocol we write by default.  May be less than HIGHEST_PROTOCOL.
# Only bump this if the oldest still supported version of Python already
# includes it.
DEFAULT_PROTOCOL = 4


class PickleError(Exception):
    """A common base class for the other pickling exceptions."""
    pass


class PicklingError(PickleError):
    """This exception is raised when an unpicklable object is passed to the
    dump() method.

    """
    pass


class UnpicklingError(PickleError):
    """This exception is raised when there is a problem unpickling an object,
    such as a security violation.

    Note that other exceptions may also be raised during unpickling, including
    (but not necessarily limited to) AttributeError, EOFError, ImportError,
    and IndexError.

    """
    pass

# An instance of _Stop is raised by Unpickler.load_stop() in response to
# the STOP opcode, passing the object that is the result of unpickling.


class _Stop(Exception):
    def __init__(self, value):
        self.value = value


# Jython has PyStringMap; it's a dict subclass with string keys
try:
    from org.python.core import PyStringMap
except ImportError:
    PyStringMap = None

# Pickle opcodes.  See pickletools.py for extensive docs.  The listing
# here is in kind-of alphabetical order of 1-character pickle code.
# pickletools groups them by purpose.

MARK = b'('   # push special markobject on stack
STOP = b'.'   # every pickle ends with STOP
POP = b'0'   # discard topmost stack item
POP_MARK = b'1'   # discard stack top through topmost markobject
DUP = b'2'   # duplicate top stack item
FLOAT = b'F'   # push float object; decimal string argument
INT = b'I'   # push integer or bool; decimal string argument
BININT = b'J'   # push four-byte signed int
BININT1 = b'K'   # push 1-byte unsigned int
LONG = b'L'   # push long; decimal string argument
BININT2 = b'M'   # push 2-byte unsigned int
NONE = b'N'   # push None
PERSID = b'P'   # push persistent object; id is taken from string arg
BINPERSID = b'Q'  # "       "         "  ;  "  "   "     "  stack
REDUCE = b'R'   # apply callable to argtuple, both on stack
STRING = b'S'   # push string; NL-terminated string argument
BINSTRING = b'T'   # push string; counted binary string argument
SHORT_BINSTRING = b'U'  # "     "   ;    "      "       "      " < 256 bytes
UNICODE = b'V'   # push Unicode string; raw-unicode-escaped'd argument
BINUNICODE = b'X'  # "     "       "  ; counted UTF-8 string argument
APPEND = b'a'   # append stack top to list below it
BUILD = b'b'   # call __setstate__ or __dict__.update()
GLOBAL = b'c'   # push self.find_class(modname, name); 2 string args
DICT = b'd'   # build a dict from stack items
EMPTY_DICT = b'}'   # push empty dict
APPENDS = b'e'   # extend list on stack by topmost stack slice
GET = b'g'   # push item from memo on stack; index is string arg
BINGET = b'h'  # "    "    "    "   "   "  ;   "    " 1-byte arg
INST = b'i'   # build & push class instance
LONG_BINGET = b'j'   # push item from memo on stack; index is 4-byte arg
LIST = b'l'   # build list from topmost stack items
EMPTY_LIST = b']'   # push empty list
OBJ = b'o'   # build & push class instance
PUT = b'p'   # store stack top in memo; index is string arg
BINPUT = b'q'  # "     "    "   "   " ;   "    " 1-byte arg
LONG_BINPUT = b'r'  # "     "    "   "   " ;   "    " 4-byte arg
SETITEM = b's'   # add key+value pair to dict
TUPLE = b't'   # build tuple from topmost stack items
EMPTY_TUPLE = b')'   # push empty tuple
SETITEMS = b'u'   # modify dict by adding topmost key+value pairs
BINFLOAT = b'G'   # push float; arg is 8-byte float encoding

TRUE = b'I01\n'  # not an opcode; see INT docs in pickletools.py
FALSE = b'I00\n'  # not an opcode; see INT docs in pickletools.py

# Protocol 2

PROTO = b'\x80'  # identify pickle protocol
NEWOBJ = b'\x81'  # build object by applying cls.__new__ to argtuple
EXT1 = b'\x82'  # push object from extension registry; 1-byte index
EXT2 = b'\x83'  # ditto, but 2-byte index
EXT4 = b'\x84'  # ditto, but 4-byte index
TUPLE1 = b'\x85'  # build 1-tuple from stack top
TUPLE2 = b'\x86'  # build 2-tuple from two topmost stack items
TUPLE3 = b'\x87'  # build 3-tuple from three topmost stack items
NEWTRUE = b'\x88'  # push True
NEWFALSE = b'\x89'  # push False
LONG1 = b'\x8a'  # push long from < 256 bytes
LONG4 = b'\x8b'  # push really big long

_tuplesize2code = [EMPTY_TUPLE, TUPLE1, TUPLE2, TUPLE3]

# Protocol 3 (Python 3.x)

BINBYTES = b'B'   # push bytes; counted binary string argument
SHORT_BINBYTES = b'C'  # "     "   ;    "      "       "      " < 256 bytes

# Protocol 4

SHORT_BINUNICODE = b'\x8c'  # push short string; UTF-8 length < 256 bytes
BINUNICODE8 = b'\x8d'  # push very long string
BINBYTES8 = b'\x8e'  # push very long bytes string
EMPTY_SET = b'\x8f'  # push empty set on the stack
ADDITEMS = b'\x90'  # modify set by adding topmost stack items
FROZENSET = b'\x91'  # build frozenset from topmost stack items
NEWOBJ_EX = b'\x92'  # like NEWOBJ but work with keyword only arguments
STACK_GLOBAL = b'\x93'  # same as GLOBAL but using names on the stacks
MEMOIZE = b'\x94'  # store top of the stack in memo
FRAME = b'\x95'  # indicate the beginning of a new frame

# Protocol 5

BYTEARRAY8 = b'\x96'  # push bytearray
NEXT_BUFFER = b'\x97'  # push next out-of-band buffer
READONLY_BUFFER = b'\x98'  # make top of stack readonly

__all__.extend([x for x in dir() if re.match("[A-Z][A-Z0-9_]+$", x)])

class _Unframer:

    def __init__(self, file_read, file_readline, file_tell=None):
        self.file_read = file_read
        self.file_readline = file_readline
        self.current_frame = None

    def readinto(self, buf):
        if self.current_frame:
            n = self.current_frame.readinto(buf)
            if n == 0 and len(buf) != 0:
                self.current_frame = None
                n = len(buf)
                buf[:] = self.file_read(n)
                return n
            if n < len(buf):
                raise UnpicklingError(
                    "pickle exhausted before end of frame")
            return n
        else:
            n = len(buf)
            buf[:] = self.file_read(n)
            return n

    def read(self, n):
        if self.current_frame:
            data = self.current_frame.read(n)
            if not data and n != 0:
                self.current_frame = None
                return self.file_read(n)
            if len(data) < n:
                raise UnpicklingError(
                    "pickle exhausted before end of frame")
            return data
        else:
            return self.file_read(n)

    def readline(self):
        if self.current_frame:
            data = self.current_frame.readline()
            if not data:
                self.current_frame = None
                return self.file_readline()
            if data[-1] != b'\n'[0]:
                raise UnpicklingError(
                    "pickle exhausted before end of frame")
            return data
        else:
            return self.file_readline()

    def load_frame(self, frame_size):
        if self.current_frame and self.current_frame.read() != b'':
            raise UnpicklingError(
                "beginning of a new frame before end of current frame")
        self.current_frame = io.BytesIO(self.file_read(frame_size))


# Tools used for pickling.

def _getattribute(obj, name):
    for subpath in name.split('.'):
        if subpath == '<locals>':
            raise AttributeError("Can't get local attribute {!r} on {!r}"
                                 .format(name, obj))
        try:
            parent = obj
            obj = getattr(obj, subpath)
        except AttributeError:
            raise AttributeError("Can't get attribute {!r} on {!r}"
                                 .format(name, obj)) from None
    return obj, parent


def whichmodule(obj, name):
    """Find the module an object belong to."""
    module_name = getattr(obj, '__module__', None)
    if module_name is not None:
        return module_name
    # Protect the iteration by using a list copy of sys.modules against dynamic
    # modules that trigger imports of other modules upon calls to getattr.
    for module_name, module in sys.modules.copy().items():
        if (module_name == '__main__'
            or module_name == '__mp_main__'  # bpo-42406
                or module is None):
            continue
        try:
            if _getattribute(module, name)[0] is obj:
                return module_name
        except AttributeError:
            pass
    return '__main__'


def encode_long(x):
    r"""Encode a long to a two's complement little-endian binary string.
    Note that 0 is a special case, returning an empty string, to save a
    byte in the LONG1 pickling context.

    >>> encode_long(0)
    b''
    >>> encode_long(255)
    b'\xff\x00'
    >>> encode_long(32767)
    b'\xff\x7f'
    >>> encode_long(-256)
    b'\x00\xff'
    >>> encode_long(-32768)
    b'\x00\x80'
    >>> encode_long(-128)
    b'\x80'
    >>> encode_long(127)
    b'\x7f'
    >>>
    """
    if x == 0:
        return b''
    nbytes = (x.bit_length() >> 3) + 1
    result = x.to_bytes(nbytes, byteorder='little', signed=True)
    if x < 0 and nbytes > 1:
        if result[-1] == 0xff and (result[-2] & 0x80) != 0:
            result = result[:-1]
    return result


def decode_long(data):
    r"""Decode a long from a two's complement little-endian binary string.

    >>> decode_long(b'')
    0
    >>> decode_long(b"\xff\x00")
    255
    >>> decode_long(b"\xff\x7f")
    32767
    >>> decode_long(b"\x00\xff")
    -256
    >>> decode_long(b"\x00\x80")
    -32768
    >>> decode_long(b"\x80")
    -128
    >>> decode_long(b"\x7f")
    127
    """
    return int.from_bytes(data, byteorder='little', signed=True)

# Unpickling machinery
def die():
    # ok theres no way you can like break all of these right...
    assert 1 == 0
    exit()
    raise _Stop


class _Unpickler:

    def __init__(self, file, *, fix_imports=True,
                 encoding="ASCII", errors="strict", buffers=None):
        """This takes a binary file for reading a pickle data stream.

        The protocol version of the pickle is detected automatically, so
        no proto argument is needed.

        The argument *file* must have two methods, a read() method that
        takes an integer argument, and a readline() method that requires
        no arguments.  Both methods should return bytes.  Thus *file*
        can be a binary file object opened for reading, an io.BytesIO
        object, or any other custom object that meets this interface.

        The file-like object must have two methods, a read() method
        that takes an integer argument, and a readline() method that
        requires no arguments.  Both methods should return bytes.
        Thus file-like object can be a binary file object opened for
        reading, a BytesIO object, or any other custom object that
        meets this interface.

        If *buffers* is not None, it should be an iterable of buffer-enabled
        objects that is consumed each time the pickle stream references
        an out-of-band buffer view.  Such buffers have been given in order
        to the *buffer_callback* of a Pickler object.

        If *buffers* is None (the default), then the buffers are taken
        from the pickle stream, assuming they are serialized there.
        It is an error for *buffers* to be None if the pickle stream
        was produced with a non-None *buffer_callback*.

        Other optional arguments are *fix_imports*, *encoding* and
        *errors*, which are used to control compatibility support for
        pickle stream generated by Python 2.  If *fix_imports* is True,
        pickle will try to map the old Python 2 names to the new names
        used in Python 3.  The *encoding* and *errors* tell pickle how
        to decode 8-bit string instances pickled by Python 2; these
        default to 'ASCII' and 'strict', respectively. *encoding* can be
        'bytes' to read these 8-bit string instances as bytes objects.
        """
        self._buffers = iter(buffers) if buffers is not None else None
        self._file_readline = file.readline
        self._file_read = file.read
        self.memo = {}
        self.encoding = encoding
        self.errors = errors
        self.proto = 0
        self.fix_imports = fix_imports

    def load(self):
        """Read a pickled object representation from the open file.

        Return the reconstituted object hierarchy specified in the file.
        """
        # Check whether Unpickler was initialized correctly. This is
        # only needed to mimic the behavior of _pickle.Unpickler.dump().
        if not hasattr(self, "_file_read"):
            raise UnpicklingError("Unpickler.__init__() was not called by "
                                  "%s.__init__()" % (self.__class__.__name__,))
        self._unframer = _Unframer(self._file_read, self._file_readline)
        self.read = self._unframer.read
        self.readinto = self._unframer.readinto
        self.readline = self._unframer.readline
        self.metastack = []
        self.stack = []
        self.append = self.stack.append
        self.proto = 0
        read = self.read
        dispatch = self.dispatch
        try:
            while True:
                key = read(1)
                if not key:
                    raise EOFError
                assert isinstance(key, bytes_types)
                dispatch[key[0]](self)
        except _Stop as stopinst:
            return stopinst.value

    # Return a list of items pushed in the stack after last MARK instruction.
    def pop_mark(self):
        items = self.stack
        self.stack = self.metastack.pop()
        self.append = self.stack.append
        return items

    def persistent_load(self, pid):
        raise UnpicklingError("unsupported persistent id encountered")

    dispatch = {}

    def load_proto(self):
        proto = self.read(1)[0]
        if not 0 <= proto <= HIGHEST_PROTOCOL:
            raise ValueError("unsupported pickle protocol: %d" % proto)
        self.proto = proto
    dispatch[PROTO[0]] = load_proto

    def load_frame(self):
        frame_size, = unpack('<Q', self.read(8))
        if frame_size > sys.maxsize:
            raise ValueError("frame size > sys.maxsize: %d" % frame_size)
        self._unframer.load_frame(frame_size)
    dispatch[FRAME[0]] = load_frame

    def load_persid(self):
        try:
            pid = self.readline()[:-1].decode("ascii")
        except UnicodeDecodeError:
            raise UnpicklingError(
                "persistent IDs in protocol 0 must be ASCII strings")
        self.append(self.persistent_load(pid))
    dispatch[PERSID[0]] = load_persid

    def load_binpersid(self):
        pid = self.stack.pop()
        self.append(self.persistent_load(pid))
    dispatch[BINPERSID[0]] = load_binpersid

    def load_none(self):
        self.append(None)
    dispatch[NONE[0]] = load_none

    def load_false(self):
        self.append(False)
    dispatch[NEWFALSE[0]] = load_false

    def load_true(self):
        self.append(True)
    dispatch[NEWTRUE[0]] = load_true

    def load_int(self):
        data = self.readline()
        if data == FALSE[1:]:
            val = False
        elif data == TRUE[1:]:
            val = True
        else:
            val = int(data, 0)
        self.append(val)
    dispatch[INT[0]] = load_int

    def load_binint(self):
        self.append(unpack('<i', self.read(4))[0])
    dispatch[BININT[0]] = load_binint

    def load_binint1(self):
        self.append(self.read(1)[0])
    dispatch[BININT1[0]] = load_binint1

    def load_binint2(self):
        self.append(unpack('<H', self.read(2))[0])
    dispatch[BININT2[0]] = load_binint2

    def load_long(self):
        val = self.readline()[:-1]
        if val and val[-1] == b'L'[0]:
            val = val[:-1]
        self.append(int(val, 0))
    dispatch[LONG[0]] = load_long

    def load_long1(self):
        n = self.read(1)[0]
        data = self.read(n)
        self.append(decode_long(data))
    dispatch[LONG1[0]] = load_long1

    def load_long4(self):
        n, = unpack('<i', self.read(4))
        if n < 0:
            # Corrupt or hostile pickle -- we never write one like this
            raise UnpicklingError("LONG pickle has negative byte count")
        data = self.read(n)
        self.append(decode_long(data))
    dispatch[LONG4[0]] = load_long4

    def load_float(self):
        self.append(float(self.readline()[:-1]))
    dispatch[FLOAT[0]] = load_float

    def load_binfloat(self):
        self.append(unpack('>d', self.read(8))[0])
    dispatch[BINFLOAT[0]] = load_binfloat

    def _decode_string(self, value):
        # Used to allow strings from Python 2 to be decoded either as
        # bytes or Unicode strings.  This should be used only with the
        # STRING, BINSTRING and SHORT_BINSTRING opcodes.
        if self.encoding == "bytes":
            return value
        else:
            return value.decode(self.encoding, self.errors)

    def load_string(self):
        data = self.readline()[:-1]
        # Strip outermost quotes
        if len(data) >= 2 and data[0] == data[-1] and data[0] in b'"\'':
            data = data[1:-1]
        else:
            raise UnpicklingError("the STRING opcode argument must be quoted")
        self.append(self._decode_string(codecs.escape_decode(data)[0]))
    dispatch[STRING[0]] = load_string

    def load_binstring(self):
        # Deprecated BINSTRING uses signed 32-bit length
        len, = unpack('<i', self.read(4))
        if len < 0:
            raise UnpicklingError("BINSTRING pickle has negative byte count")
        data = self.read(len)
        self.append(self._decode_string(data))
    dispatch[BINSTRING[0]] = load_binstring

    def load_binbytes(self):
        len, = unpack('<I', self.read(4))
        if len > maxsize:
            raise UnpicklingError("BINBYTES exceeds system's maximum size "
                                  "of %d bytes" % maxsize)
        self.append(self.read(len))
    dispatch[BINBYTES[0]] = load_binbytes

    def load_unicode(self):
        self.append(str(self.readline()[:-1], 'raw-unicode-escape'))
    dispatch[UNICODE[0]] = load_unicode

    def load_binunicode(self):
        len, = unpack('<I', self.read(4))
        if len > maxsize:
            raise UnpicklingError("BINUNICODE exceeds system's maximum size "
                                  "of %d bytes" % maxsize)
        self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
    dispatch[BINUNICODE[0]] = load_binunicode

    def load_binunicode8(self):
        len, = unpack('<Q', self.read(8))
        if len > maxsize:
            raise UnpicklingError("BINUNICODE8 exceeds system's maximum size "
                                  "of %d bytes" % maxsize)
        self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
    dispatch[BINUNICODE8[0]] = load_binunicode8

    def load_binbytes8(self):
        len, = unpack('<Q', self.read(8))
        if len > maxsize:
            raise UnpicklingError("BINBYTES8 exceeds system's maximum size "
                                  "of %d bytes" % maxsize)
        self.append(self.read(len))
    dispatch[BINBYTES8[0]] = load_binbytes8

    def load_bytearray8(self):
        len, = unpack('<Q', self.read(8))
        if len > maxsize:
            raise UnpicklingError("BYTEARRAY8 exceeds system's maximum size "
                                  "of %d bytes" % maxsize)
        b = bytearray(len)
        self.readinto(b)
        self.append(b)
    dispatch[BYTEARRAY8[0]] = load_bytearray8

    def load_next_buffer(self):
        if self._buffers is None:
            raise UnpicklingError("pickle stream refers to out-of-band data "
                                  "but no *buffers* argument was given")
        try:
            buf = next(self._buffers)
        except StopIteration:
            raise UnpicklingError("not enough out-of-band buffers")
        self.append(buf)
    dispatch[NEXT_BUFFER[0]] = load_next_buffer

    def load_readonly_buffer(self):
        buf = self.stack[-1]
        with memoryview(buf) as m:
            if not m.readonly:
                self.stack[-1] = m.toreadonly()
    dispatch[READONLY_BUFFER[0]] = load_readonly_buffer

    def load_short_binstring(self):
        len = self.read(1)[0]
        data = self.read(len)
        self.append(self._decode_string(data))
    dispatch[SHORT_BINSTRING[0]] = load_short_binstring

    def load_short_binbytes(self):
        len = self.read(1)[0]
        self.append(self.read(len))
    dispatch[SHORT_BINBYTES[0]] = load_short_binbytes

    def load_short_binunicode(self):
        len = self.read(1)[0]
        self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
    dispatch[SHORT_BINUNICODE[0]] = load_short_binunicode

    def load_tuple(self):
        items = self.pop_mark()
        self.append(tuple(items))
    dispatch[TUPLE[0]] = load_tuple

    def load_empty_tuple(self):
        self.append(())
    dispatch[EMPTY_TUPLE[0]] = load_empty_tuple

    def load_tuple1(self):
        self.stack[-1] = (self.stack[-1],)
    dispatch[TUPLE1[0]] = load_tuple1

    def load_tuple2(self):
        self.stack[-2:] = [(self.stack[-2], self.stack[-1])]
    dispatch[TUPLE2[0]] = load_tuple2

    def load_tuple3(self):
        self.stack[-3:] = [(self.stack[-3], self.stack[-2], self.stack[-1])]
    dispatch[TUPLE3[0]] = load_tuple3

    def load_empty_list(self):
        self.append([])
    dispatch[EMPTY_LIST[0]] = load_empty_list

    def load_empty_dictionary(self):
        self.append({})
    dispatch[EMPTY_DICT[0]] = load_empty_dictionary

    def load_empty_set(self):
        self.append(set())
    dispatch[EMPTY_SET[0]] = load_empty_set

    def load_frozenset(self):
        items = self.pop_mark()
        self.append(frozenset(items))
    dispatch[FROZENSET[0]] = load_frozenset

    def load_list(self):
        items = self.pop_mark()
        self.append(items)
    dispatch[LIST[0]] = load_list

    def load_dict(self):
        items = self.pop_mark()
        d = {items[i]: items[i+1]
             for i in range(0, len(items), 2)}
        self.append(d)
    dispatch[DICT[0]] = load_dict

    # INST and OBJ differ only in how they get a class object.  It's not
    # only sensible to do the rest in a common routine, the two routines
    # previously diverged and grew different bugs.
    # klass is the class to instantiate, and k points to the topmost mark
    # object, following which are the arguments for klass.__init__.
    def _instantiate(self, klass, args):
        die()  # lets not!

    def load_inst(self):
        module = self.readline()[:-1].decode("ascii")
        name = self.readline()[:-1].decode("ascii")
        klass = self.find_class(module, name)
        # /shrug alr banned _instantiate, what are you going to do
        self._instantiate(klass, self.pop_mark())
    dispatch[INST[0]] = load_inst

    def load_obj(self):
        # Stack is ... markobject classobject arg1 arg2 ...
        args = self.pop_mark()
        cls = args.pop(0)
        self._instantiate(cls, args)  # ok more _instantiate wow im so scared
    dispatch[OBJ[0]] = load_obj

    def load_newobj(self):
        die()  # nope
    dispatch[NEWOBJ[0]] = load_newobj

    def load_newobj_ex(self):
        die()  # well... no
    dispatch[NEWOBJ_EX[0]] = load_newobj_ex

    def load_global(self):
        module = self.readline()[:-1].decode("utf-8")
        name = self.readline()[:-1].decode("utf-8")
        klass = self.find_class(module, name)
        self.append(klass)
    dispatch[GLOBAL[0]] = load_global

    def load_stack_global(self):
        name = self.stack.pop()
        module = self.stack.pop()
        if type(name) is not str or type(module) is not str:
            raise UnpicklingError("STACK_GLOBAL requires str")
        self.append(self.find_class(module, name))
    dispatch[STACK_GLOBAL[0]] = load_stack_global

    def load_ext1(self):
        code = self.read(1)[0]
        self.get_extension(code)
    dispatch[EXT1[0]] = load_ext1

    def load_ext2(self):
        code, = unpack('<H', self.read(2))
        self.get_extension(code)
    dispatch[EXT2[0]] = load_ext2

    def load_ext4(self):
        code, = unpack('<i', self.read(4))
        self.get_extension(code)
    dispatch[EXT4[0]] = load_ext4

    def get_extension(self, code):
        die()  # here you can have errors!

    def find_class(self, _: str, name: str) -> object:
        # yoinked from azs chall, it was just that goated
        # Security measure -- prevent access to dangerous elements
        for x in ['exe', 'os', 'break', 'eva', 'help', 'sys', 'load', 'open', 'dis', 'lic', 'cre']: # you can have set.... ig
            if x in name:
                print("Smuggling contraband in broad daylight?! Guards!")
                break
        # Security measure -- only the main module is a valid lookup target
        else:
            __main__ = object.mgk.nested.__import__('__main__')
            # hope you didnt have getattr overwriting dreams...
            return object.__getattribute__(__main__, name)

    def load_reduce(self):
        die()  # ... do i need to even say anything here...
    dispatch[REDUCE[0]] = load_reduce

    def load_pop(self):
        if self.stack:
            del self.stack[-1]
        else:
            self.pop_mark()
    dispatch[POP[0]] = load_pop

    def load_pop_mark(self):
        self.pop_mark()
    dispatch[POP_MARK[0]] = load_pop_mark

    def load_dup(self):
        self.append(self.stack[-1])
    dispatch[DUP[0]] = load_dup

    def load_get(self):
        i = int(self.readline()[:-1])
        try:
            self.append(self.memo[i])
        except KeyError:
            msg = f'Memo value not found at index {i}'
            raise UnpicklingError(msg) from None
    dispatch[GET[0]] = load_get

    def load_binget(self):
        i = self.read(1)[0]
        try:
            self.append(self.memo[i])
        except KeyError:
            msg = f'Memo value not found at index {i}'
            raise UnpicklingError(msg) from None
    dispatch[BINGET[0]] = load_binget

    def load_long_binget(self):
        i, = unpack('<I', self.read(4))
        try:
            self.append(self.memo[i])
        except KeyError as exc:
            msg = f'Memo value not found at index {i}'
            raise UnpicklingError(msg) from None
    dispatch[LONG_BINGET[0]] = load_long_binget

    def load_put(self):
        i = int(self.readline()[:-1])
        try:
            if (i == 'setattr' or '__' in i):
                return
        except:
            pass
        if i < 0:
            raise ValueError("negative PUT argument")
        self.memo[i] = self.stack[-1]
    dispatch[PUT[0]] = load_put

    def load_binput(self):
        i = self.read(1)[0]
        try:
            if (i == 'setattr' or '__' in i):
                return
        except:
            pass
        if i < 0:
            raise ValueError("negative BINPUT argument")
        self.memo[i] = self.stack[-1]
    dispatch[BINPUT[0]] = load_binput

    def load_long_binput(self):
        i, = unpack('<I', self.read(4))
        try:
            if (i == 'setattr' or '__' in i):
                return
        except:
            pass
        if i > maxsize:
            raise ValueError("negative LONG_BINPUT argument")
        self.memo[i] = self.stack[-1]
    dispatch[LONG_BINPUT[0]] = load_long_binput

    def load_memoize(self):
        memo = self.memo
        i = len(memo)
        try:
            if (i == 'setattr' or '__' in i):
                return
        except:
            pass
        memo[i] = self.stack[-1]
    dispatch[MEMOIZE[0]] = load_memoize

    def load_append(self):
        stack = self.stack
        value = stack.pop()
        list = stack[-1]
        list.append(value)
    dispatch[APPEND[0]] = load_append

    def load_appends(self):
        items = self.pop_mark()
        list_obj = self.stack[-1]
        try:
            extend = list_obj.extend
        except AttributeError:
            pass
        else:
            extend(items)
            return
        # Even if the PEP 307 requires extend() and append() methods,
        # fall back on append() if the object has no extend() method
        # for backward compatibility.
        append = list_obj.append
        for item in items:
            append(item)
    dispatch[APPENDS[0]] = load_appends

    def load_setitem(self):
        stack = self.stack
        value = stack.pop()
        key = stack.pop()
        dict = stack[-1]
        if not (key == 'setattr' or '__' in key):
            dict[key] = value
    dispatch[SETITEM[0]] = load_setitem

    def load_setitems(self):
        items = self.pop_mark()
        dict = self.stack[-1]
        for i in range(0, len(items), 2):
            if not (items[i] == 'setattr' or '__' in items[i]):
                dict[items[i]] = items[i + 1]
    dispatch[SETITEMS[0]] = load_setitems

    def load_additems(self):
        die()
    dispatch[ADDITEMS[0]] = load_additems

    # too insecure smh
    def load_build(self):
        stack = self.stack
        state = stack.pop()
        inst = stack[-1]
    #        setstate = getattr(inst, "__setstate__", None)
    #        if setstate is not None:
    #            setstate(state)
    #            return
        slotstate = None
        if isinstance(state, tuple) and len(state) == 2:
            state, slotstate = state
        if state:
            inst_dict = inst.__dict__
            # intern = sys.intern
            for k, v in state.items():
                # if type(k) is str:
                #    inst_dict[intern(k)] = v
                # else:
                if not (k == 'setattr' or '__' in k):
                    inst_dict[k] = v
        if slotstate:
            for k, v in slotstate.items():
                setattr(inst, k, v)
    dispatch[BUILD[0]] = load_build

    def load_mark(self):
        self.metastack.append(self.stack)
        self.stack = []
        self.append = self.stack.append
    dispatch[MARK[0]] = load_mark

    def load_stop(self):
        value = self.stack.pop()
        raise _Stop(value)
    dispatch[STOP[0]] = load_stop


def _load(file, *, fix_imports=True, encoding="ASCII", errors="strict",
          buffers=None):
    return _Unpickler(file, fix_imports=fix_imports, buffers=buffers,
                      encoding=encoding, errors=errors).load()


def _loads(s, /, *, fix_imports=True, encoding="ASCII", errors="strict",
           buffers=None):
    if isinstance(s, str):
        raise TypeError("Can't load pickle from unicode string")
    file = io.BytesIO(s)
    return _Unpickler(file, fix_imports=fix_imports, buffers=buffers,
                      encoding=encoding, errors=errors).load()


# Use the faster _pickle if possible
try:
    from _pickle import (
        PickleError,
        PicklingError,
        UnpicklingError,
        Pickler,
        Unpickler,
        dump,
        dumps,
        load,
        loads
    )
except ImportError:
    Unpickler = _Unpickler
    load, loads = _load, _loads