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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 dump(*args, **kwargs):
 """Dump a numpy.ndarray to file stream. This works exactly like the usual `json.dump()` function, but it uses our custom serializer. """

    kwargs.update(dict(cls=NumpyEncoder,
                       sort_keys=True,
                       indent=4,
                       separators=(',', ': ')))
    return _json.dump(*args, **kwargs)