first demo

main.py

@@ -1,6 +1,30 @@
+# example from root.cz
+# https://www.root.cz/clanky/validace-dat-v-pythonu-s-vyuzitim-knihovny-pydantic/
+
+from models.User import User, UserNone, UserUnion, UserPositiveInt, UserFieldValidator, UserMaxLength
+
+
 def main():
     print("Hello from pydantic-demo!")
+    print(f"{User(name="John", surname="Doe", age=42, registered=True)=}")
+    print(f"{User(name="Adam", surname="Bernau", age=52, registered=True)=}")
+    print(f"{UserNone(name="Adam", surname="Bernau", age=None)=}")
+    print(f"{UserUnion(name="Adam", surname="Bernau", age=None)=}")
+    print(f"{UserUnion(name="Adam", surname="Bernau")=}")
+    print(f"{UserPositiveInt(name="Adam", surname="Bernau")=}")
+    #print(f"{UserPositiveInt(name="Adam", surname="Bernau", age=-50)=}")
+    print(f"{UserFieldValidator(name="Adam", surname="Bernau", age=18)=}")
+    print(f"{UserMaxLength(name="Adam", surname="Bernau", age=18)=}")
+    #print(f"{UserMaxLength(name="Adam", surname="Bernaukjghsmtlmgchs", age=18)=}")
 
+    # JSON
+    data = """
+        {"name": "John",
+         "surname": "Doe",
+         "age": 18
+        }
+    """
+    print(f"{UserMaxLength.model_validate_json(data)=}")
 
 if __name__ == "__main__":
     main()