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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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