How do you make long list comprehensions in python? -

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for example:

>>> [x x in range(y) y in range(z) z in range(3)] traceback (most recent call last):   file "<stdin>", line 1, in <module> nameerror: name 'y' not defined

i expect behave same as:

>>> a=[] >>> z in range(3): ...   y in range(z): ...     x in range(3): ...       a.append(x) ...  >>> [0, 1, 2, 0, 1, 2, 0, 1, 2]

but doesn't. why?

your current comprehension work if reverse order of loops:

[x z in range(3) y in range(z) x in range(3)]

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