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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 clean_build(self):
 """Delete the build directory and all ingested files """

        import shutil

        if self.build_fs.exists:
            try:
                shutil.rmtree(self.build_fs.getsyspath('/'))
            except NoSysPathError:
                pass