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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 _convert_char_to_type(self, type_char):
 """ Ensures a read character is a typecode. :param type_char: Read typecode :return: The typecode as a string (using chr) :raise RuntimeError: Unknown typecode """

        typecode = type_char
        if type(type_char) is int:
            typecode = chr(type_char)

        if typecode in self.TYPECODES_LIST:
            return typecode
        else:
            raise RuntimeError(
                "Typecode {0} ({1}) isn't supported.".format(type_char, typecode)
            )