class_docstr: Base class used to filter attributes based on their expected class.
code: def __iter__(self):
      precision_keys = [
          k
          for k, v in self.attributes.items()
          if isinstance(v, self.clazz)
      ]
      yield from precision_keys
  
imports: from collections.abc import MutableMapping
  from numbers import Integral
  from hls4ml.model.types import NamedType, Source, TensorVariable, WeightVariable
  from hls4ml.utils.string_utils import convert_to_pascal_case
label_desc: Use image node_id 4 for calling the AttributeMapping obj's underlying member method code with example usage: obj.__iter__() without return types