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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 set_bulk_size(size):
 """Set size limit on bulk execution. Bulk execution bundles many operators to run together. This can improve performance when running a lot of small operators sequentially. Parameters size : int Maximum number of operators that can be bundled in a bulk. Returns ------- int Previous bulk size. """

    prev = ctypes.c_int()
    check_call(_LIB.MXEngineSetBulkSize(
        ctypes.c_int(size), ctypes.byref(prev)))
    return prev.value