class_docstr: ElementConversion is a subclass of DataConversion providing
  concrete methods to convert a Dataset to specific Element
  types.
code: def distribution(self, dim=None, groupby=None, **kwargs):
      if groupby is None:
          groupby = []
      if dim is None:
          if self._element.vdims:
              dim = self._element.vdims[0]
          else:
              raise Exception(
                  "Must supply an explicit value dimension "
                  "if no value dimensions are defined "
              )
      if groupby:
          reindexed = self._element.reindex(groupby, [dim])
          kwargs["kdims"] = dim
          kwargs["vdims"] = None
          return reindexed.groupby(
              groupby, HoloMap, Distribution, **kwargs
          )
      else:
          element = self._element
          params = dict(
              kdims=[element.get_dimension(dim)], label=element.label
          )
          if element.group != element.param["group"].default:
              params["group"] = element.group
          return Distribution(
              (element.dimension_values(dim),), **dict(params, **kwargs)
          )
  
imports: from ..core import HoloMap
  from ..core.data import DataConversion, Dataset
  from .annotation import *
  from .chart import *
  from .chart3d import *
  from .geom import *
  from .graphs import *
  from .path import *
  from .raster import *
  from .sankey import *
  from .stats import *
  from .tabular import *
  from .tiles import *
label_desc: Use image node_id 6 for calling the ElementConversion obj's underlying member method code with example usage: obj.distribution(dim, groupby) and returns: reindexed, Distribution