Python中的“==”、“=”、“is”

“==”

tests whether objects have the same value

>>> 2.0 == 2
True
>>> 2 == 2
True

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“=”

Assign values to objects

>>> 2 = 2
  File "", line 1
SyntaxError: can't assign to literal

>>> a = 2
>>> a
2

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“is”

tests whether objects have the same identity

>>> 2 is 2
True
>>> 2 is 2.0
False

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（"Keep your eyes on the stars and your feet on the ground." --西奥多·罗斯福）