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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 no_going_back(confirmation):
 """Show a confirmation to a user. :param confirmation str: the string the user has to enter in order to confirm their action. """

    if not confirmation:
        confirmation = 'yes'

    prompt = ('This action cannot be undone! Type "%s" or press Enter '
              'to abort' % confirmation)

    ans = click.prompt(prompt, default='', show_default=False)
    if ans.lower() == str(confirmation):
        return True

    return False