* [mypy] fix type annotations for problem003/sol1 and problem003/sol3
* [mypy] fix type annotations for project euler problem007/sol2
* [mypy] fix type annotations for project euler problem008/sol2
* [mypy] fix type annotations for project euler problem009/sol1
* [mypy] fix type annotations for project euler problem014/sol1
* [mypy] fix type annotations for project euler problem 025/sol2
* [mypy] fix type annotations for project euler problem026/sol1.py
* [mypy] fix type annotations for project euler problem037/sol1
* [mypy] fix type annotations for project euler problem044/sol1
* [mypy] fix type annotations for project euler problem046/sol1
* [mypy] fix type annotations for project euler problem051/sol1
* [mypy] fix type annotations for project euler problem074/sol2
* [mypy] fix type annotations for project euler problem080/sol1
* [mypy] fix type annotations for project euler problem099/sol1
* [mypy] fix type annotations for project euler problem101/sol1
* [mypy] fix type annotations for project euler problem188/sol1
* [mypy] fix type annotations for project euler problem191/sol1
* [mypy] fix type annotations for project euler problem207/sol1
* [mypy] fix type annotations for project euler problem551/sol1
* Added solution for Project Euler problem 74. Fixes: #2695
* Added doctest for solution() in project_euler/problem_74/sol1.py
* Update docstrings and 0-padding of directory name. Reference: #3256