[Python] TypeError: Object of type Project is not JSON serializable

I am learning FastAPI.

My code:

main.py

from . import models, schemas
from .database import SessionLocal, engine

models.Base.metadata.create_all(bind=engine)

app = FastAPI()

# Dependency
def get_db():
db = SessionLocal()
try:
yield db
finally:
db.close()

@app.get("/projects/", response_model=list[schemas.ProjectSchema])
def list_project(db: Session = Depends(get_db)):
""" Get all projects"""
projects = db.query(models.Project).all()
print("XXX_ ", projects) # XXX_ [<src.models.Project ...]
return JSONResponse(content={"message": projects})


models.py

from sqlalchemy import Column, Integer, String
from sqlalchemy.orm import relationship
from .database import Base

class Project(Base):
__tablename__ = "projects"
id = Column(Integer, primary_key=True)
name = Column(String, nullable=False, unique=True)


schemas.py

from typing import List, Union
from pydantic import BaseModel

class ProjectSchema(BaseModel):
name: str
class Config:
orm_mode = True


I have an error for GET /projects request:

TypeError: Object of type Project is not JSON serializable
​

I have read FastAPI TypeError: Object of type 'ModelMetaclass' is not JSON serializable.

I checked that response_model=list[schemas.ProjectSchema] is OK. How to fix the error?

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