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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def weld_udf(weld_template, mapping):
 """Create WeldObject to encode weld_template code given mapping. Parameters weld_template : str Weld code to encode. mapping : dict Which substitutions to make in the weld_template. Returns ------- WeldObject Representation of this computation. """

    weld_obj = create_empty_weld_object()

    for k, v in mapping.items():
        if isinstance(v, (np.ndarray, WeldObject)):
            obj_id = get_weld_obj_id(weld_obj, v)
            mapping.update({k: obj_id})

    weld_obj.weld_code = weld_template.format(**mapping)

    return weld_obj