Added is-perm

Added is-perm, a quick efficient way to check that two iterables are permutations of each other.

snippets/python/s/is-perm.md

@@ -0,0 +1,27 @@
+---
+title: Check if two iterables are permutations of each other
+type: snippet
+language: python
+tags: [list]
+cover: apples
+dateModified: 2023-05-23 10:48:03 +0100
+---
+
+Check if two iterables are permutations of each other.
+
+- Use `Counter` to verify that each element in both iterables appear an equal number of times.
+
+```py
+from collections import Counter
+
+def is_perm(items0, items1):
+  return len(items0) == len(items1) and Counter(items0) == Counter(items1)
+```
+
+```py
+is_perm([1, 2, 3], [4, 1, 6]) # False
+is_perm([1, 2], [2, 1]) # True
+
+is_perm("dad", "add") # True
+is_perm("snack", "track") # False
+```