What's the difference between expression and statement using Python yield [duplicate]

Question

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Expression Versus Statement

What's the difference between expression and statement in Python?

I have never thought of this question until I am learning Python generator that said "use yield as an expression"

Also, can you explain this question in the context of Python generator that 'use yield as an expression'?

Answer 1

An expression can be evaluated to return a value. Any expression can also be used as a statement.

To put it another way, if you can write a = ..., then ... is an expression. So 2*3 and zip(x,y) are expressions.

Something like raise Exception is a statement but not an expression: you can't write a = (raise Exception).

yield being an expression means that b = (yield a) is valid code in a generator. If you use the generator's send() method, b is set to the value you pass in.