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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 _pickle_load(path):
 """ Loads pickled topology. Careful with Python versions though! """

        _, ext = os.path.splitext(path)
        topology = None
        if sys.version_info.major == 2:
            if ext == '.pickle2':
                with open(path, 'rb') as f:
                    topology = pickle.load(f)
            elif ext in ('.pickle3', '.pickle'):
                with open(path, 'rb') as f:
                    topology = pickle.load(f, protocol=3)
        elif sys.version_info.major == 3:
            if ext == '.pickle2':
                with open(path, 'rb') as f:
                    topology = pickle.load(f)
            elif ext in ('.pickle3', '.pickle'):
                with open(path, 'rb') as f:
                    topology = pickle.load(f)
        if topology is None:
            raise ValueError('File {} is not compatible with this version'.format(path))
        return topology