from pydantic import BaseModel, Field class Model(BaseModel): # Required undefined_default_no_args: int = Field() undefined_default: int = Field(description='my desc') positional_ellipsis_default: int = Field(...) named_ellipsis_default: int = Field(default=...) # Not required positional_default: int = Field(1) named_default: int = Field(default=2) named_default_factory: int = Field(default_factory=lambda: 3) Model()