[Python] Mapper class between API and DB field properties

I would like to implement a kind of mapper between db data and some other data like obtained from the response of API.

The expected behavior is following:

class IData:
a: str = ('db_a', 'type_a')
b: str = ('db_b', 'type_b')
c: str = ('db_c', 'type_c')

class MyData(IData):
a = 'api_a'
b = 'api_b'
c = 'api_c'

m = MyData() # or `m = MyData`

m.a.db_name -> 'db_a'
m.a.db_type -> 'db_b'
m.a.api_name -> 'db_c'

m.get_db_names() -> ['db_a', 'db_b', 'db_c']
m.get_db_types() -> ['type_a', 'type_b', 'type_c']
m.get_api_names() -> ['api_a', 'api_b', 'api_c'] # or Nones if some are not assigned in MyData definition


I implemented it like following:

class _Field:
def __init__(self, db_name, db_type, api_name=None):
self.db_name = db_name
self.db_type = db_type
self.api_name = api_name

class _base:
def get_db_names(self):
return [self.__dict__.db_name for i in self.__dict__ if not i.startswith("_")]
def get_db_types(self):
return [self.__dict__.db_type for i in self.__dict__ if not i.startswith("_")]
def get_api_names(self):
return [self.__dict__.api_name for i in self.__dict__ if not i.startswith("_")]

class IData(_base):
def __init__(self):
self.a = _Field("db_a", "type_a")
self.b = _Field("db_b", "type_b")
self.c = _Field("db_c", "type_c")

class MyData(IData):
def __init__(self):
super().__init__()
self.a.api_name = "api_a"
self.b.api_name = "api_b"
self.c.api_name = "api_c"


Is there some better, simpler, more robust solution using dataclasses or types (namespaces) or something else?

Also would be nice to rise an exception if for some attribute the api_name is not set in class MyData(IData) when the user is instantiating m = MyData()

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