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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 set_rate_BC(self, pores, values):
 r""" Apply constant rate boundary conditons to the specified pore locations. This is similar to a Neumann boundary condition, but is slightly different since it's the conductance multiplied by the gradient, while Neumann conditions specify just the gradient. Parameters pores : array_like The pore indices where the condition should be applied values : scalar or array_like The value to of the boundary condition. If a scalar is supplied it is assigne to all locations, and if a vector is applied it corresponds directy to the locations given in ``pores``. Notes ----- The definition of ``quantity`` is specified in the algorithm's ``settings``, e.g. ``alg.settings['quentity'] = 'pore.pressure'``. """

        self._set_BC(pores=pores, bctype='rate', bcvalues=values, mode='merge')