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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 yes_or_no(message):
 """Gets user input and returns True for yes and False for no."""

    while True:
        print message, '(yes/no)',
        line = raw_input()
        if line is None:
            return None
        line = line.lower()
        if line == 'y' or line == 'ye' or line == 'yes':
            return True
        if line == 'n' or line == 'no':
            return False