[Python] Does the extra comma at the end of a dictionary, list or set has any special meaning...

I noticed by chance that adding an extra separator comma at the end of a list, dictionary or set is syntactically correct and does not seem to add anything to the data structure:

In [1]: d1 = {'a': 1, 'b': 2}

In [2]: d2 = {'c': 10, 'd': 20,}

In [3]: d1
Out[3]: {'a': 1, 'b': 2}

In [4]: d2
Out[4]: {'c': 10, 'd': 20}


Does it have any special meaning or usage?
The only one I found is to explicit a data structure during an initialization:

In [14]: r = (1)

In [15]: r
Out[15]: 1

In [16]: r = (1,)

In [17]: r
Out[17]: (1,)

Continue reading...