src/codewars/PandasTutorial.py

@@ -0,0 +1,21 @@
+import pandas as pd
+
+
+def export_csv_with_name_and_grade(student_name: str, grade: str):
+    students_df = pd.read_csv("files/students.csv", index_col=False)
+    grades_df = pd.read_csv("files/grades.csv", index_col=False)
+
+    students_grades_df = students_df.merge(
+        grades_df, left_on="Student_ID", right_on="ID"
+    )
+
+    solution = students_grades_df[
+        (students_grades_df["Name"] == student_name)
+        & (students_grades_df["Grade"] == grade)
+    ]
+
+    solution[["Student_ID", "Class"]].to_csv("files/output.csv", index=False)
+
+
+if __name__ == "__main__":
+    export_csv_with_name_and_grade("Bob", "A")

src/codewars/SimpleWebFramework.py

@@ -0,0 +1,54 @@
+import typing
+
+
+class Router(object):
+
+    def __init__(self):
+        self.routes = {}
+
+    def bind(self, path: str, method: str, func: typing.Callable):
+        self.routes[(path, method)] = func
+
+    def run_request(self, path: str, method: str):
+        return self.routes.get((path, method), lambda: "Error 404: Not Found")()
+
+
+if __name__ == "__main__":
+    # Should handle GET routes'
+    router = Router()
+    router.bind("/hello", "GET", lambda: "hello world")
+    router.bind("/login", "GET", lambda: "Please log-in.")
+
+    assert router.run_request("/hello", "GET") == "hello world"
+    assert router.run_request("/login", "GET") == "Please log-in."
+
+    # Should handle POST routes
+    router = Router()
+    router.bind("/vote", "POST", lambda: "Voted.")
+    router.bind("/comment", "POST", lambda: "Comment sent.")
+
+    assert router.run_request("/vote", "POST") == "Voted."
+    assert router.run_request("/comment", "POST") == "Comment sent."
+
+    # Should handle mixed routes.
+    router = Router()
+    router.bind("/login", "GET", lambda: "Please log-in.")
+    router.bind("/login", "POST", lambda: "Logging-in.")
+
+    assert router.run_request("/login", "GET") == "Please log-in."
+    assert router.run_request("/login", "POST") == "Logging-in."
+
+    # Should return 404 for non-existing routes.
+    router = Router()
+    assert (
+        router.run_request("/this-url-does-not-exist", "GET") == "Error 404: Not Found"
+    )
+
+    # Should modify existing routes
+    router = Router()
+    router.bind("/page", "GET", lambda: "First binding.")
+    router.bind("/page", "GET", lambda: "Modified binding.")
+
+    assert router.run_request("/page", "GET") == "Modified binding."
+
+    print("All tests passed!")

src/codewars/WhoLikesIt.py

@@ -0,0 +1,24 @@
+def likes(names):
+    match len(names):
+        case 0:
+            return "no one likes this"
+        case 1:
+            return f"{names[0]} likes this"
+        case 2:
+            return f"{names[0]} and {names[1]} like this"
+        case 3:
+            return f"{names[0]}, {names[1]} and {names[2]} like this"
+        case _:
+            return f"{names[0]}, {names[1]} and {len(names) - 2} others like this"
+
+
+if __name__ == "__main__":
+    assert likes([]) == "no one likes this"
+    assert likes(["Peter"]) == "Peter likes this"
+    assert likes(["Jacob", "Alex"]) == "Jacob and Alex like this"
+    assert likes(["Max", "John", "Mark"]) == "Max, John and Mark like this"
+    assert (
+        likes(["Alex", "Jacob", "Mark", "Max"]) == "Alex, Jacob and 2 others like this"
+    )
+
+    print("All tests passed!")

src/codewars/files/grades.csv

@@ -0,0 +1,8 @@
+ID,Class,Grade
+32155,English,A
+32155,History,B
+32155,Science,B
+43226,English,C
+43226,Math,A
+43226,Science,A
+43226,History,B

src/codewars/files/output.csv

@@ -0,0 +1,2 @@
+Student_ID,Class
+32155,English

src/codewars/files/students.csv

@@ -0,0 +1,3 @@
+Name,Student_ID
+Bob,32155
+Ron,43226