Iterate over the keys of a dictionary:
In [4]: hsh = {'a': 1, 'b': 2} In [5]: for k in hsh: print( k) ...: a b
Iterate over the keys-value pairs of a dictionary:
In [1]: hsh = {'a': 1, 'b': 2} In [2]: for k,v in hsh.iteritems(): ...: print( k, v) ...: a 1 b 2