wrapped.py

from typing import (
    Generic,
    Type,
    TypeVar,
)

class Statement(object):
   pass
 
S = TypeVar("S", bound=Statement)


class Bla(Generic[S]):

    def __init__(
        self,
        statement_type: Type[S] = Statement,
    ):
        self.statement_type = statement_type
    
    def make(self) -> S:
        return self.statement_type()