def is_mul(var):
    if var.owner and var.owner.op == tensor.mul:
        return var.owner.inputs
    else:
        return None
Return a mock for attribute *attr_name* on *cls* where the patch is
dataset/ETHPy150Open rizar/attention-lvcsr/libs/Theano/theano/tensor/nnet/sigm.py/is_mul--crossover with--dataset/ETHPy150Open python-openxml/python-docx/tests/unitutil/mock.py/cls_attr_mock