Add generics exercise using List[Person] for type-safe children attribute

Author: AFatmaa

generics.py

@@ -0,0 +1,19 @@
+from dataclasses import dataclass
+from typing import List
+
+@dataclass(frozen=True)
+class Person:
+    name: str
+    age: int
+    children: List["Person"]
+
+fatma = Person(name="Fatma", age=7, children=[])
+aisha = Person(name="Aisha", age=5, children=[])
+imran = Person(name="Imran", age=35, children=[fatma, aisha])
+
+def print_family_tree(person: Person) -> None:
+    print(person.name)
+    for child in person.children:
+        print(f"- {child.name} ({child.age})")
+
+print_family_tree(imran)