docs: def mslike(pop, **kwargs):
      """
      Function to establish default parameters
      for a single-locus simulation for standard pop-gen
      modeling scenarios.
  
      :params pop: An instance of :class:`fwdpy11.DiploidPopulation`
      :params kwargs: Keyword arguments.
      """
      import fwdpy11
      if isinstance(pop, fwdpy11.DiploidPopulation) is False:
          raise ValueError("incorrect pop type: " + str(type(pop)))
      defaults = {'simlen': 10*pop.N,
                  'beg': 0.0,
                  'end': 1.0,
                  'theta': 100.0,
                  'pneutral': 1.0,
                  'rho': 100.0,
                  'dfe': None
                  }
      for key, value in kwargs.items():
          if key in defaults:
              defaults[key] = value
      import numpy as np
  
      params = {'demography': np.array([pop.N]*defaults['simlen'],
                dtype=np.uint32),
                'nregions': [fwdpy11.Region(defaults['beg'],
                             defaults['end'], 1.0)],
                'recregions': [fwdpy11.Region(defaults['beg'],
                               defaults['end'], 1.0)],
                'rates': ((defaults['pneutral']*defaults['theta'])/(4.0*pop.N),
                          ((1.0-defaults['pneutral'])*defaults['theta']) /
                          (4.0*pop.N),
                          defaults['rho']/(4.0*float(pop.N))),
                'gvalue': fwdpy11.Multiplicative(2.0)
                }
      if defaults['dfe'] is None:
          params['sregions'] = []
      else:
          params['sregions'] = [defaults['dfe']]
      return params