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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 num_throats(self, labels='all', mode='union'):
 r""" Return the number of throats of the specified labels Parameters labels : list of strings, optional The throat labels that should be included in the count. If not supplied, all throats are counted. mode : string, optional Specifies how the count should be performed. The options are: **'or', 'union', 'any'** : (default) Throats with *one or more* of the given labels are counted. **'and', 'intersection', 'all'** : Throats with *all* of the given labels are counted. **'xor', 'exclusive_or'** : Throats with *only one* of the given labels are counted. **'nor', 'none', 'not'** : Throats with *none* of the given labels are counted. **'nand'** : Throats with *some but not all* of the given labels are counted. **'xnor'** : Throats with *more than one* of the given labels are counted. Returns ------- Nt : int Number of throats with the specified labels See Also -------- num_pores count Notes ----- Technically, *'nand'* and *'xnor'* should also count throats with *none* of the labels, however, to make the count more useful these are not included. """

        # Count number of pores of specified type
        Ts = self._get_indices(labels=labels, mode=mode, element='throat')
        Nt = sp.shape(Ts)[0]
        return Nt