old_contents: from lightning.types.base import Base
  from lightning.types.decorators import viztype
  from lightning.types.utils import vecs_to_points_three, add_property
  
  @viztype
  class Particles(Base):
  
      _name = 'particles'
  
      @staticmethod
      def clean(x, y, z, color=None, label=None):
          """
          Plot three-dimensional data as points.
  
          .. image:: particles.png
  
          Parameters
          ----------
          x, y, z : array-like, each (n,)
              Input data
  
          color : array-like, optional, singleton or (n,3)
              Single rgb value or array to set colors
          """
  
          points = vecs_to_points_three(x, y, z)
          outdict = {'points': points}
  
          outdict = add_property(outdict, color, 'color')
          outdict = add_property(outdict, label, 'label')
  
          return outdict
new_contents: from lightning.types.base import Base
  from lightning.types.decorators import viztype
  from lightning.types.utils import vecs_to_points_three, add_property
  
  @viztype
  class Particles(Base):
  
      _name = 'particles'
  
      @staticmethod
      def clean(x, y, z, color=None, label=None, alpha=None, size=None):
          """
          Plot three-dimensional data as points.
  
          .. image:: particles.png
  
          Parameters
          ----------
          x, y, z : array-like, each (n,)
              Input data
  
          color : array-like, optional, singleton or (n,3)
              Single rgb value or array to set colors
  
          label : array-like, optional, singleton or (n,)
              Single integer or array to set colors via groups
  
          size : array-like, optional, singleton or (n,)
              Single size or array to set point sizes
  
          alpha : array-like, optional, singleton or (n,)
              Single alpha value or array to set fill and stroke opacity
  
          """
  
          points = vecs_to_points_three(x, y, z)
          outdict = {'points': points}
  
          outdict = add_property(outdict, color, 'color')
          outdict = add_property(outdict, label, 'label')
          outdict = add_property(outdict, size, 'size')
          outdict = add_property(outdict, alpha, 'alpha')
  
          return outdict
subject: add size / alpha to particles