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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 wheel_metadata(self):
 """Get the distribution metadata of an unpacked wheel distribution."""

        if not self.is_wheel:
            raise TypeError("Requirement is not a wheel distribution!")
        for distribution in find_distributions(self.source_directory):
            return distribution
        msg = "pkg_resources didn't find a wheel distribution in %s!"
        raise Exception(msg % self.source_directory)