heyong.fu
37 lines
902 B
Python
37 lines
902 B
Python
obj_x = [10, 20]
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obj_y = [10, 20]
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print(obj_x == obj_y) # True 比较内容
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print(obj_x is obj_y) # False 比较内存地址
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# 定义一个列表，并让另一个变量引用它
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obj_p = [30, 40]
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obj_q = obj_p # obj_q 引用了 obj_p 所指向的同一个对象
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print(obj_p == obj_q) # True 比较内容
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print(obj_p is obj_q) # True 比较内存地址
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# is not None 判断一个变量是否为None
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my_variable = None
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if my_variable is not None:
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# 如果 my_variable 不是 None，则打印此消息
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print("Variable is not None")
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else:
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# 如果 my_variable 是 None，则打印此消息
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print("Variable is None")
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# 错误示范：使用 != None 进行比较
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# if my_variable != None:
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# 如果 my_variable 不等于 None，则打印此消息
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# print("Variable is not None (using != None)")
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sum = 0
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for i in range(5):
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if i == 2:
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continue
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sum += i
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print(sum)
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