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Printing and recursion, a printer for list, tuple and dictionary

Over the time I've followed on PyPi on Twitter, there has been a number of entries regarding printing of lists. Now I know there is a pprint module and that it works well, but I decided to see if I could create a one-function printer of lists (and dictionaries as well) with the help of recursion.

Some 30 minutes later I ended up with this:

import types

def printer(data, prefix='', prefix_extend='  ',
            sequence_types = (types.ListType, types.TupleType),
            dictionary_type = types.DictionaryType):
    if type(data) in sequence_types:
        for item in data:
            if not type(item) in sequence_types:
                if not type(item) == dictionary_type:
                    print prefix, item
                else:
                    printer(item, prefix=prefix+prefix_extend,
                            prefix_extend=prefix_extend)
            else:
                printer(item, prefix=prefix+prefix_extend,
                        prefix_extend=prefix_extend)
    if type(data) == dictionary_type:
        for key, value in data.items():
            if not type(value) == dictionary_type:
                if not type(value) in sequence_types:
                    print prefix, key, ':', value
                else:
                    printer(value, prefix=prefix+prefix_extend,
                            prefix_extend=prefix_extend)
            else:
                print prefix+prefix_extend, key, ':'
                printer(value, prefix=prefix+prefix_extend+prefix_extend,
                        prefix_extend=prefix_extend)

data = [1,2,3, [4,5, [6,7] ], {'a':1, 'b':{'c':3, 'd':{1:1}}}]
printer(data)

And the output is what you'd expect:

 1
 2
 3
   4
   5
     6
     7
   a : 1
     b :
       c : 3
         d :
           1 : 1

Now, if you're working with deeply nested sequences and dictionaries, it might be an idea to go more object oriented.. but that depends. d:]

Any better ones?

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