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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_as_nullable_float(self, key):
 """ Converts map element into a float or returns None if conversion is not possible. :param key: an index of element to get. :return: float value of the element or None if conversion is not supported. """

        value = self.get(key)
        return FloatConverter.to_nullable_float(value)