python: iterate over dictionary sorted by key

Question

I have a Python dictionary

steps = {1:"value1", 5:"value2", 2:"value3"} 

I need to iterate over this sorted by key.

I tried this:

x = sorted(steps, key=lambda key: steps[key]) 

but the values are gone from x.

Answer 1

I need to iterate over this is sorted order by the key.

I think lambdas is overkill here, try this:

>>> steps = {1:"val1", 5:"val2", 2:"val3"} >>> >>> for key in sorted(steps): ...     print steps[key] ... val1 val3 val2 

Answer 2

You need to iterate over steps.items(), because an iteration over dict only returns its keys.

>>> x = sorted(steps.items()) >>> x [(1, 'value1'), (2, 'value3'), (5, 'value2')] 

Iterate over sorted keys:

>>> for key in sorted(steps): ...     # use steps[keys] to get the value