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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 _default_objc(self):
 """ Load the objc library using ctypes. """

        objc = ctypes.cdll.LoadLibrary(find_library('objc'))
        objc.objc_getClass.restype = ctypes.c_void_p
        objc.sel_registerName.restype = ctypes.c_void_p
        objc.objc_msgSend.restype = ctypes.c_void_p
        objc.objc_msgSend.argtypes = [ctypes.c_void_p, ctypes.c_void_p]
        return objc