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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 find_connecting_throat(self, P1, P2):
 r""" Return the throat index connecting pairs of pores Parameters P1 , P2 : array_like The indices of the pores whose throats are sought. These can be vectors of indices, but must be the same length Returns ------- Returns a list the same length as P1 (and P2) with the each element containing the throat index that connects the corresponding pores, or `None`` if pores are not connected. Notes ----- The returned list can be converted to an ND-array, which will convert the ``None`` values to ``nan``. These can then be found using ``scipy.isnan``. Examples -------- [None, 1, None] """

        am = self.create_adjacency_matrix(weights=self.Ts, fmt='coo')
        sites = sp.vstack((P1, P2)).T
        Ts = topotools.find_connecting_bonds(sites=sites, am=am)
        return Ts