'Add the given ``field`` under the given ``name`` in the class'

@api.model
def _add_field(self, name, field):

    cls = type(self)
    if (not isinstance(getattr(cls, name, field), Field)):
        _logger.warning('In    model    %r,    field    %r    overriding    existing    value', cls._name, name)
    setattr(cls, name, field)
    cls._fields[name] = field
    field.setup_base(self, name)
