flatten_dict.py

import collections

def flatten_dict(l):
    d = {}
    for k, v in l.items():
        if isinstance(v, collections.Mapping):
            d.update(flatten_dict(v))
        elif isinstance(v, list) or isinstance(v, tuple):
            for i, l in enumerate(v):
                d[k+'_{}'.format(i)] = l
        else:
            d[k] = v
    return d