Diff work incorrect with the same field names in different models

If two different models have same field names eg
class ModelOne(Base):
    __tablename__ = 'model_one'

    fieldname = Column(Integer)

class ModelOne(Base):
    __tablename__ = 'model_two'

    fieldname = Column(String)

With use api.make_update_script_for_model we have ValueError

line 220, in genB2AMigration
    for modelCol, databaseCol in td.columns_different:
ValueError: too many values to unpack