Lists in Python -

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i noticed can multiply list scalar behavior weird if multiply: 

[2,3,4] * 3

i get:
[2,3,4,2,3,4,2,3,4]
understand results it's for? there other weird operations that?

the main purpose of operand initialisation. example, if want initialize list 20 equal numbers can using loop:

arr=[] in range(20):     arr.append(3)

an alternative way using operator:

arr = [3] * 20

more weird , normal list operation on lists can find here http://www.discoversdk.com/knowledge-base/using-lists-in-python


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