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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 regexp_prompt(prompt, regexp='.', answer=''):
    '''Ask the user for a text entry that matches a regular expression

       Parameters
       ==========
       prompt: the prompt to ask the user
       regexp: the regular expression to match. defaults to anything.
    
    '''
    get_input = getattr(__builtins__, 'raw_input', input)
    while not re.search(regexp, answer):
        answer = get_input(prompt + ': ').strip()
        # If the option isn't valid, this is shown next
        message = "Your entry must match the regular expression %s" %regexp    

    return answer