📝 Add source examples for Python 3.9 and 3.10 (#715)

* 📝 Add source examples for Python 3.9 and 3.10

* ✅ Add tests for new source examples for Python 3.9 and 3.10, still needs pytest markers

* ✅ Add tests for fastapi examples

* ✅ Update tests for FastAPI app testing, for Python 3.9 and 3.10, fixing multi-app testing conflicts

* ✅ Require Python 3.9 and 3.10 for tests

* ✅ Update tests with missing markers

docs_src/tutorial/connect/create_tables/tutorial001_py310.py

@@ -0,0 +1,34 @@
+from sqlmodel import Field, SQLModel, create_engine
+
+
+class Team(SQLModel, table=True):
+    id: int | None = Field(default=None, primary_key=True)
+    name: str = Field(index=True)
+    headquarters: str
+
+
+class Hero(SQLModel, table=True):
+    id: int | None = Field(default=None, primary_key=True)
+    name: str = Field(index=True)
+    secret_name: str
+    age: int | None = Field(default=None, index=True)
+
+    team_id: int | None = Field(default=None, foreign_key="team.id")
+
+
+sqlite_file_name = "database.db"
+sqlite_url = f"sqlite:///{sqlite_file_name}"
+
+engine = create_engine(sqlite_url, echo=True)
+
+
+def create_db_and_tables():
+    SQLModel.metadata.create_all(engine)
+
+
+def main():
+    create_db_and_tables()
+
+
+if __name__ == "__main__":
+    main()