How to Flatten Nested Python For Loops

Python Tip: Use product from itertools to flatten your nested for loops.

Here is an example 👇

devices = ["192.168.1.1", "192.168.1.2", "192.168.1.3"]
interfaces = ["Gi0/1", "Gi0/2", "Gi0/3"]

# -- Using nested loops --
for d in devices:
    for i in interfaces:
        print(d, i)

# ... instead use itertools.product():

# -- Using itertools --
from itertools import product

for d, i in product(devices, interfaces):
    print(d, i)
# Output:
# 192.168.1.1 Gi0/1
# 192.168.1.1 Gi0/2
# 192.168.1.1 Gi0/3
# 192.168.1.2 Gi0/1
# 192.168.1.2 Gi0/2
# 192.168.1.2 Gi0/3