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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 find_sources(self):
 """Generate SOURCES.txt manifest file"""

        manifest_filename = os.path.join(self.egg_info, "SOURCES.txt")
        mm = manifest_maker(self.distribution)
        mm.manifest = manifest_filename
        mm.run()
        self.filelist = mm.filelist