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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 parse_magnitude(self, magnitude_str):
 """ Converts magnitude field to a float value, or ``None`` if GCVS does not list the magnitude. Returns a tuple (magnitude, symbol), where symbol can be either an empty string or a single character - one of '<', '>', '('. """

        symbol = magnitude_str[0].strip()
        magnitude = magnitude_str[1:6].strip()
        return float(magnitude) if magnitude else None, symbol