2026年深度解析：为什么 `is None` 才是 Python 代码的黄金标准

在 Python 的日常开发中，我们经常需要判断一个变量是否为空。作为开发者，你可能习惯性地写下一行代码：

if x == None:
    ...

或者，你可能见过更有经验的同事这样写：

CODEBLOCKe77ae5b7INLINECODE0b5a3e35xINLINECODE02649225NoneINLINECODE0a765b47is NoneINLINECODEc89ac011==INLINECODE4d9576c2a == bINLINECODE6d3d1bd6aINLINECODEdba9e6a6eqINLINECODE75e29c2fa.eq(b)INLINECODEad883409isINLINECODE2d2fbb97a is bINLINECODE311ed498id(a) == id(b)INLINECODE8e0fba67is NoneINLINECODE5b81d933is NoneINLINECODEf8443ecbNoneINLINECODEdc8551c4NoneINLINECODE21a482b9NoneINLINECODE19ecff72is NoneINLINECODE580be5adNoneINLINECODE7436f3d7a is NoneINLINECODE286791e4aINLINECODE86632185NoneINLINECODEa2c6d0b1isINLINECODE824f5f03==INLINECODE62bdebc9is NoneINLINECODEfa7ae460datalistINLINECODE9cd63fa0emptydataINLINECODEc9b721cfNoneINLINECODE63697d18is NoneINLINECODE6dc1dfd9== NoneINLINECODEa39e3a87eqINLINECODE4381b5aa== NoneINLINECODE970c3d23x == NoneINLINECODE7b6add0fx.eq(None)INLINECODE154d6aaexINLINECODE283f0e9eeqINLINECODEbf8c6941NoneINLINECODE1064cd5c== NoneINLINECODE2d5814b3== NoneINLINECODE6b72644bvalINLINECODE287ef834NoneINLINECODEac8ad016None.eq(None)INLINECODE7b6c4dc1TrueINLINECODE73b9ddcc==INLINECODE9ca0f37bobj == NoneINLINECODE7e33462cTrueINLINECODE714f6fb3objINLINECODE8db6f11ceqINLINECODEe83f1ca0TrueINLINECODE677d5bebobjINLINECODEa47a0b5bNoneINLINECODEbfafdd4c==INLINECODE813a7371obj is NoneINLINECODE131ff393FalseINLINECODE28601bbeisINLINECODE5cd8e2b7objINLINECODE1b56ff59AlwaysEqualINLINECODE7192a0f1NoneINLINECODE60342598NoneTypeINLINECODE1f27d2cdisINLINECODE71ae3068NoneINLINECODE553a3441isINLINECODEe8085358==INLINECODE6da1359ceqINLINECODE37ef4323is NoneINLINECODE6a5d5fceeqINLINECODE2e34e663is NoneINLINECODEa4afb54f== NoneINLINECODE72cf55b3eqINLINECODEc1070429eqINLINECODE4f05ee29isINLINECODE01bb7d9e==INLINECODE3f32d6b7NoneINLINECODE68d87a01NoneINLINECODE9f35d23bisINLINECODE8f95475eif data == None:INLINECODEc1d83b08dataINLINECODE313acbbaeqINLINECODEfca03502NoneINLINECODEc4101437is NoneINLINECODE82b46c9bisINLINECODE0803329b==INLINECODE15e80e05isINLINECODE3d8974e5isINLINECODEeb77490dNoneINLINECODE33623bd3TrueINLINECODE20768cccFalseINLINECODEd0c5630c==INLINECODEa36ed55bis NoneINLINECODE108472da== NoneINLINECODE865621a5isINLINECODE766aad87==INLINECODE8b3a7eceeqINLINECODE5c7e2c1cis NoneINLINECODE67863cf8== NoneINLINECODE02269581eqINLINECODEa2c8dec5is NoneINLINECODE416c4f06== NoneINLINECODE3f69d783is NoneINLINECODEf9edfd62== None。将其替换为 is None`，并思考一下：如果这个变量将来被替换为一个自定义类的实例，或者由 AI 帮你重构了代码逻辑，新的写法是否会更加安全？希望你享受这次对 Python 细节的探索之旅！