import itertools
GEcontracts = ('GEH7.CME', 'GEM7.CME', 'GEU7.CME', 'GEZ7.CME', 'GEH8.CME')
print(tuple(itertools.combinations(GEcontracts, 2)))
'''
output is:
(('GEH7.CME', 'GEM7.CME'), ('GEH7.CME', 'GEU7.CME'), ('GEH7.CME', 'GEZ7.CME'), ('GEH7.CME', 'GEH8.CME'), ('GEM7.CME', 'GEU7.CME')...