code: def hist2d(x, y, label=None, opacity=None):
      
      x = np.atleast_1d(x)
      y = np.atleast_1d(y)
      data = [go.Histogram2d(x=x, y=y, opacity=opacity, name=label)]
      return Chart(data=data)
docs: 2D Histogram.
  
      Parameters
      ----------
      x : array-like, optional
      y : array-like, optional
      label : TODO, optional
      opacity : float, optional
  
      Returns
      -------
      Chart