If you only want a single item’s count, use the
>>> [1, 2, 3, 4, 1, 4, 1].count(1) 3
Important: this is very slow if you are counting multiple different items
count call goes over the entire list of
n elements. Calling
count in a loop
n times means
n * n total checks, which can be catastrophic for performance.
If you want to count multiple items, use
Counter, which only does
n total checks.