d1 = {"a1": {"b11": "0", "b12": "1"}, "a2": {"b21": "2", "b22": "3"}, "a3": {"b32": "3"}}
d2 = {"a1": {"b11": "4", "b12": "1"}, "a2": {"b21": "2", "b22": "3"}, "a3": {"b32": "3"}, "a4": {"b41": "5"}}

def compare_dictionaries(dict_1, dict_2, dict_1_name, dict_2_name, path=""):
err = ''
key_err = ''
value_err = ''
old_path = path
for k in dict_1.keys():
    path = old_path + "[%s]" % k
    if not dict_2.has_key(k):
        key_err += "Key %s%s not in %sn" % (dict_2_name, path, dict_2_name)
    else:
        if isinstance(dict_1[k], dict) and isinstance(dict_2[k], dict):
            err += compare_dictionaries(dict_1[k],dict_2[k],'d1','d2', path)
        else:
            if dict_1[k] != dict_2[k]:
                value_err += "Value of %s%s (%s) not same as %s%s (%s)n"
                    % (dict_1_name, path, dict_1[k], dict_2_name, path, dict_2[k])

for k in dict_2.keys():
    path = old_path + "[%s]" % k
    if not dict_1.has_key(k):
        key_err += "Key %s%s not in %sn" % (dict_2_name, path, dict_1_name)

return key_err + value_err + err


print compare_dictionaries(d1, d2, 'dict1', 'dict2')

dict2[a4] not in dict1
Value of dict1[a1][b11] (0) not same as dict2[a1][b11] (4)
Value of dict1[a2][b22] (3) not same as dict2[a2][b22] (6)

................................
| d1           |   d2          |
--------------------------------
| Changed:                     |
| [a1][b11]=0  |  [a1][b11]=4  |
| [a2][b22]=3  |  [a2][b22]=6  |
| Unique:                      |
|              |  [a4]         |
````````````````````````````````