I can't find imap() in itertools in Python

Question

itertools.imap() is in Python 2, but not in Python 3.

Actually, that function was moved to just the map function in Python 3 and if you want to use the old Python 2 map, you must use list(map()).

If you want something that works in both Python 3 and Python 2, you can do something like:

try:
    from itertools import imap
except ImportError:
    # Python 3...
    imap=map

You are using Python 3, therefore there is no imap function in itertools module. It was removed, because global function map now returns iterators.

How about this?

imap = lambda *args, **kwargs: list(map(*args, **kwargs))

In fact!! :)

import itertools
itertools.imap = lambda *args, **kwargs: list(map(*args, **kwargs))

I like the python-future idoms for universal Python 2/3 code, like this:

# Works in both Python 2 and 3:
from builtins import map

You then have to refactor your code to use map everywhere you were using imap before:

myiter = map(func, myoldlist)

# `myiter` now has the correct type and is interchangeable with `imap`
assert isinstance(myiter, iter)

You do need to install future for this to work on both 2 and 3:

pip install future

You can use the 2to3 script (https://docs.python.org/2/library/2to3.html) which is part of every Python installation to translate your program or whole projects from Python 2 to Python 3.

python <path_to_python_installation>\Tools\scripts\2to3.py -w <your_file>.py

(-w option writes modifications to file, a backup is stored)