Insert at first position of a list in Python

python list insert
Fr0z3n7 picture Fr0z3n7 · Feb 21, 2014 · Viewed 234.7k times · Source

How can I insert an element at the first index of a list ? If I use list.insert(0,elem), do elem modify the content of the first index? Or do I have to create a new list with the first elem and then copy the old list inside this new one?

Answer

michel-slm picture michel-slm · Feb 21, 2014

Use insert:

In [1]: ls = [1,2,3]

In [2]: ls.insert(0, "new")

In [3]: ls
Out[3]: ['new', 1, 2, 3]

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