Parse a name-serialized enum from a string.

parse_enum.py

from enum import Enum
from typing import TypeVar, Type

E = TypeVar('E', bound=Enum)


def parse_enum(enum_type: Type[E], enum_name:str) -> E:
    try:
        for known_e_name, enum_val in enum_type._member_map_.items():
            if enum_name == known_e_name:
                return enum_val
        raise ValueError(f"Could not parse '{enum_name}' into a value of enum '{enum_type}'")
    except AttributeError as e:
        raise ValueError(f"Is enum type ('{enum_type}') actually an enum?", e)

if __name__ == "__main__":
    E1 = Enum('E1', ['a','b','c'])
    print(parse_enum(E1, 'a'))
    
    class E2(Enum):
        w, x, y, z = range(4)
    print(parse_enum(E2, 'w'))