AttributeError: module 'sqlalchemy.orm' has no attribute 'DeclarativeMeta'

This error occurs when you try to use the Declarative Base class in SQLAlchemy but the import statement is incorrect.

To fix this error, make sure you are importing the Declarative Base class from the correct module, which is sqlalchemy.ext.declarative. The correct import statement should be:

from sqlalchemy.ext.declarative import declarative_base
Base = declarative_base()

Then, you can use the Base class to define your SQLAlchemy models:

from sqlalchemy import Column, Integer, String
from sqlalchemy.ext.declarative import declarative_base

Base = declarative_base()

class User(Base):
    __tablename__ = 'users'

    id = Column(Integer, primary_key=True)
    name = Column(String)
    email = Column(String)

This should resolve the AttributeError and allow you to use the Declarative Base class in your SQLAlchemy code.