code: def add_single_feature_methods(cls):
      
      # Sanity check: This only makes sense if we are building the GAPIC
      # subclass and have enums already attached.
      if not hasattr(cls, "enums"):
          return cls
  
      # Add each single-feature method to the class.
      for feature in cls.enums.Feature.Type:
          # Sanity check: Do not make a method for the falsy feature.
          if feature.name == "TYPE_UNSPECIFIED":
              continue
  
          # Assign the appropriate metadata to the function.
          detect = _create_single_feature_method(feature)
  
          # Assign a qualified name to the function, and perform module
          # replacement on the docstring.
          detect.__qualname__ = "{cls}.{name}".format(
              cls=cls.__name__, name=detect.__name__
          )
          detect.__doc__ = detect.__doc__.format(module=cls.__module__)
  
          # Place the function on the class being created.
          setattr(cls, detect.__name__, detect)
  
      # Done; return the class.
      return cls
docs: Custom decorator intended for :class:`~vision.helpers.VisionHelpers`.
  
      This metaclass adds a `{feature}` method for every feature
      defined on the Feature enum.