Found solution to rotate_image, wrote simple test

garrison_exercises/rotate_image/rotate_image.py

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+"""
+https://leetcode.com/problems/rotate-image/
+
+You are given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise).
+
+You have to rotate the image in-place, which means you have to modify the input 2D matrix directly. DO NOT allocate another 2D matrix and do the rotation.
+"""
+
+from typing import List
+
+
+class Solution:
+    def rotate(self, matrix: List[List[int]]) -> None:
+        n = len(matrix)
+        """
+        Do not return anything, modify matrix in-place instead.
+        """
+        # Note: // means floor division in Python i.e
+        # rounding down to the nearest integer
+
+        for i in range(n // 2 + n %2):
+            for j in range(n // 2):
+                temp = matrix[n - 1 - j][i]
+                matrix[n - 1 - j][i] = matrix[n - 1 - i][n - j - 1]
+                matrix[n - 1 - i][n - j - 1] = matrix[j][n - 1 - i]
+                matrix[j][n - 1 - i] = matrix[i][j]
+                matrix[i][j] = temp

garrison_exercises/rotate_image/rotate_image_test.py

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+#from leetcode_practice.garrison_exercises.rotate_image.rotate_image import Solution
+"""
+import pathlib
+filepath = pathlib.Path(__file__).absolute() # gets the path of the current file
+"""
+
+import sys
+from typing import List
+
+from .rotate_image import *
+
+def test_size4_matrix() -> None:
+    input_matrix: List[List[int]] = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
+    output_matrix: List[List[int]] = [[7, 4, 1], [8, 5, 2], [9, 6, 3]]
+    assert(Solution.rotate(input_matrix) == [[7, 4, 1], [8, 5, 2], [9, 6, 3]])
+