teste2.py

import re

## Search for pattern 'iii' in string 'piiig'.
## All of the pattern must match, but it may appear anywhere.
## On success, match.group() is matched text.
match = re.search(r'iii', 'piiig') # found, match.group() == "iii"
match = re.search(r'igs', 'piiig') # not found, match == None

## . = any char but \n
match = re.search(r'..g', 'piiig') # found, match.group() == "iig"

## \d = digit char, \w = word char
match = re.search(r'\d\d\d', 'p123g') # found, match.group() == "123"
match = re.search(r'\w\w\w', '@@abcd!!') # found, match.group() == "abc"





## i+ = one or more i's, as many as possible.
match = re.search(r'pi+', 'piiig') # found, match.group() == "piii"

## Finds the first/leftmost solution, and within it drives the +
## as far as possible (aka 'leftmost and largest').
## In this example, note that it does not get to the second set of i's.
match = re.search(r'i+', 'piigiiii') # found, match.group() == "ii"

## \s* = zero or more whitespace chars
## Here look for 3 digits, possibly separated by whitespace.
match = re.search(r'\d \s* \d \s* \d', 'xx1 2   3xx') # found, match.group() == "1 2   3"
match = re.search(r'\d \s* \d \s* \d', 'xx12  3xx') # found, match.group() == "12  3"
match = re.search(r'\d \s* \d \s* \d', 'xx123xx') # found, match.group() == "123"

## ^ = matches the start of string, so this fails:
match = re.search(r'^b\w+', 'foobar') # not found, match == None
## but without the ^ it succeeds:
match = re.search(r'b\w+', 'foobar') # found, match.group() == "bar"

if match:
  print('found', match.group())  # 'found word:cat'
else:
  print('did not find')