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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 is_separator(self, char):
 """ Test if a character is a separator. Parameters char : str The character to test. Returns ------- ret : bool True if character is a separator, False otherwise. """

        if len(char) > 1:
            raise TypeError("Expected a char.")
        if char in self.separators:
            return True
        return False