docs: def prior_sediment_memory(*args, **kwargs):
          """Get the prior density of sediment memory
  
          Returns
          -------
          y : ndarray
              Array giving the density.
          x : ndarray
              Array of Memory (ratio) values over which the density was evaluated.
          """
          # "plot the prior for the memory (= accumulation rate varibility between neighbouring depths)"
          # PlotMemPrior @ Bacon.R ln 114 -> ln 1119 - 1141
          # w_a = mem_strength * mem_mean, w_b = mem_strength * (1 - mem_mean)
          # TODO(brews): Check that these stats are correctly translated to scipy.stats distribs.
          mem_shape = kwargs['mem_strength']  # aka. `mem_shape`
          mem_mean = kwargs['mem_mean']
          x = np.linspace(0, 1, 100)
          y = stats.beta.pdf(x, a=mem_shape * mem_mean,
                             b=mem_shape * (1 - mem_mean))
          return y, x