Как выполнить группировку в SQLAlchemy?

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from sqlalchemy import create_engine, Column, Integer, String
from sqlalchemy.orm import sessionmaker
from sqlalchemy.ext.declarative import declarative_base

engine = create_engine('sqlite:///example.db')
Session = sessionmaker(bind=engine)
Base = declarative_base()

class Person(Base):
    __tablename__ = 'people'
    id = Column(Integer, primary_key=True)
    name = Column(String)
    age = Column(Integer)

Base.metadata.create_all(engine)

session = Session()

people = session.query(Person.name, Person.age).group_by(Person.age).all()

for p in people:
    print(p.name, p.age)

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from sqlalchemy import create_engine, Column, Integer, String
from sqlalchemy.orm import sessionmaker
from sqlalchemy.ext.declarative import declarative_base

engine = create_engine('sqlite:///example.db')
Session = sessionmaker(bind=engine)
Base = declarative_base()

class Person(Base):
    __tablename__ = 'people'
    id = Column(Integer, primary_key=True)
    name = Column(String)
    age = Column(Integer)

Base.metadata.create_all(engine)

session = Session()

# Группировка записей по возрасту и подсчет количества людей в каждой группе
from sqlalchemy import func
from sqlalchemy.orm import aliased

# Создаем псевдоним для таблицы Person
person_alias = aliased(Person)

grouped_people = session.query(Person.age, func.count(person_alias.id)).    join(person_alias, Person.age == person_alias.age).    group_by(Person.age).all()

for age, count in grouped_people:
    print("Возраст:", age, "Количество людей:", count)