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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_fp_arg(self, arg):
 """ This should take a SimFunctionArgument instance and return whether or not that argument is a floating-point argument. Returns True for MUST be a floating point arg, False for MUST NOT be a floating point arg, None for when it can be either. """

        if arg in self.int_args:
            return False
        if arg in self.fp_args or arg == self.FP_RETURN_VAL:
            return True
        return None