How to pretty print nested dictionaries?

My first thought was that the JSON serializer is probably pretty good at nested dictionaries, so I'd cheat and use that:

>>> import json>>> print(json.dumps({'a':2, 'b':{'x':3, 'y':{'t1': 4, 't2':5}}},...                  sort_keys=True, indent=4)){    "a": 2,    "b": {        "x": 3,        "y": {            "t1": 4,            "t2": 5        }    }}

I'm not sure how exactly you want the formatting to look like, but you could start with a function like this:

def pretty(d, indent=0):   for key, value in d.items():      print('\t' * indent + str(key))      if isinstance(value, dict):         pretty(value, indent+1)      else:         print('\t' * (indent+1) + str(value))

You could try YAML via PyYAML. Its output can be fine-tuned. I'd suggest starting with the following:

print yaml.dump(data, allow_unicode=True, default_flow_style=False)

The result is very readable; it can be also parsed back to Python if needed.

Edit:

Example:

>>> import yaml>>> data = {'a':2, 'b':{'x':3, 'y':{'t1': 4, 't2':5}}}>>> print yaml.dump(data, default_flow_style=False)a: 2b:  x: 3  y:    t1: 4    t2: 5