def _is_junction(arg):
    return isinstance(arg, dict) and len(arg) == 1 and next(six.iterkeys(arg)) == 'junction'
Zeroing a row in the matrix should set the diagonal to the given
dataset/ETHPy150Open saltstack/salt/salt/modules/syslog_ng.py/_is_junction--crossover with--dataset/ETHPy150Open OP2/PyOP2/test/unit/test_matrices.py/TestMatrices.test_zero_rows