A script to correct sentences

sentence_fixer.py

import re

def replace(match):
	if match:
		phrase = match.group(0)
		symbol = match.group(1)
		return symbol + ' ' + phrase[-1].upper() if symbol is '.' else phrase[-1]
	
def parse(string):
    string = re.sub(r'([\.\,\?\:\;])\w', replace, string) # add space between any punctuation symbol and letter
    string = string.capitalize() # Capitalize first letter of the sentence
    string = re.sub(r'([\.])[\s]+\w', replace, string) # Capitalize any letter after a full stop
    string = re.sub(r'[\s]+', ' ', string) # Fix more than one whitespace occurrence
    return string



if __name__ == '__main__':
    print(parse('first, solve the problem.then, write the code.'))
    print(parse('this is a test... and another test.'))