help: pandas and 2d table

Hi everyone.
I state that I don't know anything about 'pandas' but I intuited that
it could do what I want. I get, through the "read_excel" method, a
table similar to this:
       obj| foo1 foo2 foo3 foo4 foo5 foo6
       -----------------------------------
      foo1|   aa   ab   zz   ad   ae   af
          |
      foo2|   ba   bb   bc   bd   zz   bf
          |
      foo3|   ca   zz   cc   cd   ce   zz
          |
      foo4|   da   db   dc   dd   de   df
          |
      foo5|   ea   eb   ec   zz   ee   ef
          |
      foo6|   fa   fb   fc   fd   fe   ff
And I would like to get a result similar to this:
{
     'zz':[('foo1','foo3'),
           ('foo2','foo5'),
           ('foo3','foo2'),
           ('foo3','foo6'),
           ('foo5','foo4')
          ]
}
Would you show me the path, please?
Thank you in advance.