Remove add_metaclass

holoviews/core/accessors.py

@@ -10,8 +10,6 @@
 
 import param
 
-from param.parameterized import add_metaclass
-
 from . import util
 from .pprint import PrettyPrinter
 
@@ -85,8 +83,7 @@ def pipelined_call(*args, **kwargs):
         return pipelined_call
 
 
-@add_metaclass(AccessorPipelineMeta)
-class Apply:
+class Apply(metaclass=AccessorPipelineMeta):
     """
     Utility to apply a function or operation to all viewable elements
     inside the object.
@@ -288,8 +285,7 @@ def transform(self, *args, **kwargs):
         return self.__call__('transform', **kwargs)
 
 
-@add_metaclass(AccessorPipelineMeta)
-class Redim:
+class Redim(metaclass=AccessorPipelineMeta):
     """
     Utility that supports re-dimensioning any HoloViews object via the
     redim method.
@@ -488,8 +484,7 @@ def values(self, specs=None, **ranges):
         return self._redim('values', specs, **ranges)
 
 
-@add_metaclass(AccessorPipelineMeta)
-class Opts:
+class Opts(metaclass=AccessorPipelineMeta):
 
     def __init__(self, obj, mode=None):
         self._mode = mode

holoviews/core/data/__init__.py

@@ -8,7 +8,7 @@
 import param
 import pandas as pd # noqa
 
-from param.parameterized import add_metaclass, ParameterizedMetaclass
+from param.parameterized import ParameterizedMetaclass
 
 from ..accessors import Redim
 from ..dimension import (
@@ -236,8 +236,7 @@ def pipelined_fn(*args, **kwargs):
         return pipelined_fn
 
 
-@add_metaclass(PipelineMeta)
-class Dataset(Element):
+class Dataset(Element, metaclass=PipelineMeta):
     """
     Dataset provides a general baseclass for Element types that
     contain structured data and supports a range of data formats.
@@ -290,7 +289,7 @@ class to each underlying element.
             cls.param.warning(cls, msg.format(class_name=class_name, apply_args=apply_args))
             return data.apply(cls, per_element=True, kdims=kdims, vdims=vdims, **kwargs)
         else:
-            return super(Dataset, cls).__new__(cls)
+            return super().__new__(cls)
 
     def __init__(self, data, kdims=None, vdims=None, **kwargs):
         from ...operation.element import (
@@ -332,7 +331,7 @@ def __init__(self, data, kdims=None, vdims=None, **kwargs):
         initialized = Interface.initialize(type(self), data, kdims, vdims,
                                            datatype=kwargs.get('datatype'))
         (data, self.interface, dims, extra_kws) = initialized
-        super(Dataset, self).__init__(data, **dict(kwargs, **dict(dims, **extra_kws)))
+        super().__init__(data, **dict(kwargs, **dict(dims, **extra_kws)))
         self.interface.validate(self, validate_vdims)
 
         # Handle _pipeline property
@@ -369,7 +368,7 @@ def __init__(self, data, kdims=None, vdims=None, **kwargs):
 
     def __getstate__(self):
         "Ensures pipelines are dropped"
-        obj_dict = super(Dataset, self).__getstate__()
+        obj_dict = super().__getstate__()
         if '_pipeline' in obj_dict:
             pipeline = obj_dict['_pipeline']
             obj_dict['_pipeline'] = pipeline.instance(operations=pipeline.operations[:1])
@@ -1195,21 +1194,21 @@ def clone(self, data=None, shared_data=True, new_type=None, link=True,
         elif self._in_method and 'dataset' not in overrides:
             overrides['dataset'] = self.dataset
 
-        return super(Dataset, self).clone(data, shared_data, new_type, *args, **overrides)
+        return super().clone(data, shared_data, new_type, *args, **overrides)
 
     # Overrides of superclass methods that are needed so that PipelineMeta
     # will find them to wrap with pipeline support
     @wraps(Dimensioned.options)
     def options(self, *args, **kwargs):
-        return super(Dataset, self).options(*args, **kwargs)
+        return super().options(*args, **kwargs)
 
     @wraps(LabelledData.map)
     def map(self, *args, **kwargs):
-        return super(Dataset, self).map(*args, **kwargs)
+        return super().map(*args, **kwargs)
 
     @wraps(LabelledData.relabel)
     def relabel(self, *args, **kwargs):
-        return super(Dataset, self).relabel(*args, **kwargs)
+        return super().relabel(*args, **kwargs)
 
     @property
     def iloc(self):

holoviews/plotting/plotly/callbacks.py

@@ -1,7 +1,5 @@
 from weakref import WeakValueDictionary
 
-from param.parameterized import add_metaclass
-
 from ...streams import (
     Stream, Selection1D, RangeXY, RangeX, RangeY, BoundsXY, BoundsX, BoundsY,
     SelectionXY
@@ -38,8 +36,7 @@ def __call__(cls, *args, **kwargs):
         return inst
 
 
-@add_metaclass(PlotlyCallbackMetaClass)
-class PlotlyCallback:
+class PlotlyCallback(metaclass=PlotlyCallbackMetaClass):
 
     def __init__(self, plot, streams, source, **params):
         self.plot = plot