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• convert dict of dicts to list of dicts
• Convert a dictionary of dataframes to a big dataframe

In [1]:
d = {'sun': 1,
     'mon': 2,
     'tue': 3}
d
Out[1]:
{'sun': 1, 'mon': 2, 'tue': 3}

To merge two python dictionaries

def merge_two_dicts(x, y):
    '''
    Given two dicts, merge them into a new dict as a shallow copy.
    For common keys, the values in y take precedence over values in x.
    '''
    z = x.copy()
    z.update(y)
    return z

Sample usage:

>>> x = {'a': 1, 'b': 2}
>>> y = {'b': 3, 'c': 4}
>>> z = merge_two_dicts(x, y)
>>> z
{'a': 1, 'c': 4, 'b': 3}

To merge an undefined number of dicts

def merge_dicts(*dict_args):
    '''
    Given any number of dicts, shallow copy and merge into a new dict,
    precedence goes to key value pairs in latter dicts.
    '''
    result = {}
    for dictionary in dict_args:
        result.update(dictionary)
    return result

Given dicts a to g

z = merge_dicts(a, b, c, d, e, f, g) 

will give a new dict z with all the key-value pairs. If same key exists in multiple dictionaries, the right most one will take precedence.

Ref:- http://stackoverflow.com/questions/38987/how-to-merge-two-python-dictionaries-in-a-single-expression