add solution for euler problem 89

Author: coryallegory

DIRECTORY.md

@@ -650,6 +650,8 @@
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_67/sol1.py)
   * Problem 76
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_76/sol1.py)
+  * Problem 89
+    * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_89/sol1.py)
   * Problem 97
     * [Sol1](https://github.com/TheAlgorithms/Python/blob/master/project_euler/problem_97/sol1.py)
   * Problem 99

project_euler/problem_89/__init__.py

@@ -0,0 +1 @@
+#