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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 get_char(prompt=None):
 """ Read a line of text from standard input and return the equivalent char; if text is not a single char, user is prompted to retry. If line can't be read, return None. """

    while True:
        s = get_string(prompt)
        if s is None:
            return None
        if len(s) == 1:
            return s[0]

        # Temporarily here for backwards compatibility
        if prompt is None:
            print("Retry: ", end="")