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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 from_file(filename, file_format="xyz"):
 """ Uses OpenBabel to read a molecule from a file in all supported formats. Args: filename: Filename of input file file_format: String specifying any OpenBabel supported formats. Returns: BabelMolAdaptor object """

        mols = list(pb.readfile(str(file_format), str(filename)))
        return BabelMolAdaptor(mols[0].OBMol)