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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 float_format(self, value):
 """Validate and set the upper case flag."""

        if isinstance(value, str):
            # Duck-test the format string; raise ValueError on fail
            '{0:{1}}'.format(1.23, value)

            self._float_format = value
        else:
            raise TypeError('Floating point format code must be a string.')