On 2013/09/20 3:44 AM, Varoquaux wrote:
> In lib/matplotlib/axes/_axes.py:
>
>>
>> -        To automatically generate the legend from labels::
>> +            line, = ax.plot([1, 2, 3], label='Inline label')
>
> Ah, nice. Thanks

It's a common idiom, and I use it, but with hesitation; it "looks wrong" 
at first glance, as you noticed.  The alternative, explicitly indexing 
with [0] at the end, is less concise but more visually obvious. 
Therefore it might be preferable in documentation intended for newcomers.