Format and print list of tuples as one line

Question

I have a list containing tuples that is generated from a database query and it looks something like this.

[(item1, value1), (item2, value2), (item3, value3),...]

The tuple will be mixed length and when I print the output it will look like this.

item1=value1, item2=value2, item3=value3,...

I have looked for a while to try to find a solution and none of the .join() solutions I have found work for this type of situation.

Answer 1

You're after something like:

>>> a = [('val', 1), ('val2', 2), ('val3', 3)]
>>> ', '.join('{}={}'.format(*el) for el in a)
'val=1, val2=2, val3=3'

This also doesn't care what type the tuple elements are... you'll get the str representation of them automatically.

Answer 2

You can use itertools as well

from itertools import starmap
', '.join(starmap('{}={}'.format, a))

Answer 3

If each tuple is only an (item, value) pair then this should work:

l = [(item1, value1), (item2, value2), (item3, value3), ...]
', '.join('='.join(t) for t in l)
'item1=value1, item2=value2, item3=value3, ...'

Answer 4

Try this:

lst = [('item1', 'value1'), ('item2', 'value2'), ('item3', 'value3')]
print ', '.join(str(x) + '=' + str(y) for x, y in lst)

I'm explicitly converting to string the items and values, if one (or both) are already strings you can remove the corresponding str() conversion:

print ', '.join(x + '=' + y for x, y in lst)

Answer 5

One possible solution is this, definitely the shortest code

>>> a = [('val', 1), ('val2', 2), ('val3', 3)]
>>>', '.join('%s=%s' % v for v in a)
'val=1, val2=2, val3=3'

works with python 2.7 as well