def _parse_string(value):

    return None if value == 'null' else value
Tests the path specification initialization.
dataset/ETHPy150Open dcos/dcos-cli/dcos/jsonitem.py/_parse_string--crossover with--dataset/ETHPy150Open log2timeline/dfvfs/tests/path/vmdk_path_spec.py/VMDKPathSpecTest.testInitialize