def test_no_circular_imports() -> None:
    """Runs the test in a subprocess because cirq has already been imported
    before in an earlier test but this test needs to control the import process.
    """
    status = subprocess.call([sys.executable, __file__])
    if status == FAIL_EXIT_CODE:  # pragma: no cover
        raise Exception('Invalid import. See captured output for details.')
    elif status != 0:  # pragma: no cover
        raise RuntimeError('Error in subprocess')
Runs the test in a subprocess because cirq has already been imported
    before in an earlier test but this test needs to control the import process.
    
dev_tools/import_test.py