Pythonic syntax to concatenate the keys and values of a dictionary

Question

I have a dictionary similar to this one

dic1 = {'Name': 'John', 'Time': 'morning'}

I want to concatenante the keys and values with a "_" separator with the following schema:

Name_John_Time_morning

This is equivalent to key1_value1_key2_value2

I have tried the following line of code but without success

x + "_" + v for x,v in dict1.keys(), dict1.values()

Answer 1

I like comprehensions better

result = '_'.join(x + '_' + y for x, y in dic1.items())

or

result = '_'.join('{}_{}'.format(*p) for p in dic1.items())

The latter form also works when there are non-string keys or values.

To ensure the output is sorted,

result = '_'.join('{}_{}'.format(*p) for p in sorted(dic1.items()))

Answer 2

Using map with str.join:

>>> dic1 = {'Name': 'John', 'Time': 'morning'}
>>> '_'.join(map('_'.join, dic1.items()))
'Name_John_Time_morning'

or using generator expression instead of map:

>>> '_'.join('_'.join(item) for item in dic1.items())
'Name_John_Time_morning'

BTW, dict is not ordered. So result may vary.