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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def _exact_match(response, matches, insensitive, fuzzy):
    '''
    returns an exact match, if it exists, given parameters
    for the match
    '''
    for match in matches:
        if response == match:
            return match
        elif insensitive and response.lower() == match.lower():
            return match
        elif fuzzy and _exact_fuzzy_match(response, match, insensitive):
            return match
    else:
        return None