<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def pytorch_id(node):
 """Returns a unique ID for a node."""

    # After ONNX simplification, the scopeName is not unique anymore
    # so append node outputs to guarantee uniqueness
    return node.scopeName() + "/outputs/" + "/".join([o.uniqueName() for o in node.outputs()])