Replacing words matching regular expressions

Takes long time to move on this because of lack of knowledge.

First I created replacer.py the put under the root of Python27. However, I got following error.

>>> from replacer import *
Traceback (most recent call last):
  File "&lt;stdin>", line 1, in &lt;module>
ImportError: No module named replacer

Teacher Google game me a solution. I didn't import sys in advance.

>>> import sys
>>> print sys.path
['', 'C:\\WINDOWS\\system32\\python27.zip', 'C:\\Python27\\DLLs', 'C:\\Python27\
\lib', 'C:\\Python27\\lib\\plat-win', 'C:\\Python27\\lib\\lib-tk', 'C:\\Python27
', 'C:\\Python27\\lib\\site-packages']
>>> from replacers import *
Traceback (most recent call last):
  File "&lt;stdin>", line 1, in &lt;module>
  File "replacers.py", line 19
    def replace(self, repl) in self.patterns:
                             ^
SyntaxError: invalid syntax
>>>

Oops, sytax error found. After a couple of try & errors, I got a following results.

>>> from replacers import *
>>> replacer = RegexpReplacer()
>>> replacer.replace("Can't is a contraction")
'Ca not is a contraction'
>>> replacer.replace("can't is a contraction")
'cannot is a contraction'
>>> replacer.replace("I should've done that thing I didn't do")
'I should have done that thing I did not do'

(I will add some more here when I have time...)