ex16.py

from sys import argv

script, filename = argv

print "We're going to erase %r." % filename
print "If you don't want that, hit CTRL-C (^C)."
print "If you do want that, hit RETURN."

raw_input("?")

print "Opening the file..."
target = open(filename, 'w')

print "Truncating the file. Goodbye!"
target.truncate()

print # this use for empty space
print "Now I'm going to ask you for three lines."

line1 = raw_input("line 1: ")
line2 = raw_input("line 2: ")
line3 = raw_input("line 3: ")

print # this use for empty space
print "I'm going to write these to the file."

# In order to avoid too much repetition in the file
# we use strings, formats, and escapes to print out
# line1, line2, line3 with just one target.write()
# command instead of six.
target.write("%s\n%s\n%s\n" % (line1, line2, line3))

# Using multilines comment to avoid repetitive use of
# target.write() command and make it as comments.
'''
target.write("\n")
target.write(line2)
target.write("\n")
target.write(line3)
target.write("\n")
'''

print "And finally, we close it."
target.close()