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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 egg_name(self):
 """Return what this distribution's standard .egg filename should be"""

        filename = "%s-%s-py%s" % (
            to_filename(self.project_name), to_filename(self.version),
            self.py_version or PY_MAJOR
        )

        if self.platform:
            filename += '-' + self.platform
        return filename