def get_equiv_var(self, obj):
        """If the given object is equivalent to some defined variable,
        return the variable, or None otherwise.
        """
        names = self._get_names(obj)
        if len(names) != 1:
            return None
        ind = self._get_ind(names[0])
        vs = self.ind_to_var.get(ind, [])
        return vs[0] if vs != [] else None
If the given object is equivalent to some defined variable,
        return the variable, or None otherwise.
        
numba/parfors/array_analysis.py