Save an extra fetch by storing the data fetched for page 1

[leo-dor]

Small change to pagination mechanism - when loading pagination info, data for page 1 is loaded but currently not stored. When asking for page 1, the data is loaded - again. Example script:

import discogs_client
d = discogs_client.Client('ExampleApplication/0.1')
d.verbose = True

a = d.artist(251558)
print "Iterating over releases..."
for r in a.releases:
    pass

Output without this change shows an extra fetch:
Iterating over releases...
GET https://api.discogs.com/artists/251558
GET https://api.discogs.com/artists/251558/releases?per_page=50&page=1
GET https://api.discogs.com/artists/251558/releases?per_page=50&page=1
GET https://api.discogs.com/artists/251558/releases?per_page=50&page=2
...

After the fix, page 1 is no longer loaded twice:
Iterating over releases...
GET https://api.discogs.com/artists/251558
GET https://api.discogs.com/artists/251558/releases?per_page=50&page=1
GET https://api.discogs.com/artists/251558/releases?per_page=50&page=2
...

[rodneykeeling]

Would you mind unindenting these last 2 lines? We indent by 4 spaces and generally like to keep the ending parenthesis/bracket/etc. aligned with where it opens. i.e.,

self._pages[1] = [
    self._transform(item) for item in data[self._list_key]
]

[leo-dor]

Fixed the spacing - sorry, that was a sloppy copy-paste.

[rodneykeeling]

Awesome, thanks! Looks good to me! Thanks for the optimization, @leo-dor! 👍