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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 _union_copy(dict1, dict2):
 """ Internal wrapper to keep one level of copying out of play, for efficiency. Only copies data on dict2, but will alter dict1. """


    for key, value in dict2.items():
        if key in dict1 and isinstance(value, dict):
            dict1[key] = _union_copy(dict1[key], value)
        else:
            dict1[key] = copy.deepcopy(value)
    return dict1