define has_path in networkx if it is not already defined
define has_path in networkx if it is not already defined

serge-sans-paille/pythran,pbrunet/pythran,artas360/pythran,hainm/pythran,pbrunet/pythran,pombredanne/pythran,artas360/pythran,pombredanne/pythran,artas360/pythran,hainm/pythran,hainm/pythran,pombredanne/pythran,serge-sans-paille/pythran,pbrunet/pythran