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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 unshare(flags):
 """ Disassociate parts of the process execution context. :param flags int: A bitmask that specifies which parts of the execution context should be unshared. """

    res = lib.unshare(flags)
    if res != 0:
        _check_error(ffi.errno)