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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 write_file(self, filename, file_format="xyz"):
 """ Uses OpenBabel to output all supported formats. Args: filename: Filename of file to output file_format: String specifying any OpenBabel supported formats. """

        mol = pb.Molecule(self._obmol)
        return mol.write(file_format, filename, overwrite=True)