Erro ao definir variáveis x e y

logo após definir dados = pd.read_csv(uri).drop(columns=["Unnamed: 0"], axis=1)

O Seguinte erro acontece ao definir as variáveis x e y:

x = dados ["preco", "idade_do_modelo", "km_por_ano"]
y = dados ["vendido"]
---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
/usr/local/lib/python3.7/dist-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance)
   2897             try:
-> 2898                 return self._engine.get_loc(casted_key)
   2899             except KeyError as err:

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

KeyError: ('preco', 'idade_do_modelo', 'km_por_ano')

The above exception was the direct cause of the following exception:

KeyError                                  Traceback (most recent call last)
2 frames
/usr/local/lib/python3.7/dist-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance)
   2898                 return self._engine.get_loc(casted_key)
   2899             except KeyError as err:
-> 2900                 raise KeyError(key) from err
   2901 
   2902         if tolerance is not None:

KeyError: ('preco', 'idade_do_modelo', 'km_por_ano')