Suggest to loosen the dependency on twitter

[Agnes-U]

Hi, your project chirps requires "twitter==1.17.1" in its dependency. After analyzing the source code, we found that the following versions of twitter can also be suitable without affecting your project, i.e., twitter 1.18.0. Therefore, we suggest to loosen the dependency on twitter from "twitter==1.17.1" to "twitter>=1.17.1,<=1.18.0" to avoid any possible conflict for importing more packages or for downstream projects that may use chirps.

May I pull a request to further loosen the dependency on twitter?

By the way, could you please tell us whether such dependency analysis may be potentially helpful for maintaining dependencies easier during your development?

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We also give our detailed analysis as follows for your reference:

Your project chirps directly uses 4 APIs from package twitter.

twitter.stream.TwitterStream.__init__, twitter.oauth.OAuth.__init__, twitter.api.TwitterHTTPError.__init__, twitter.api.Twitter.__init__

Beginning from the 4 APIs above, 12 functions are then indirectly called, including 5 twitter's internal APIs and 7 outsider APIs. The specific call graph is listed as follows (neglecting some repeated function occurrences).

[/schedutron/chirps]
+--twitter.stream.TwitterStream.__init__
|      +--twitter.stream.handle_stream_response
|      |      +--urllib2.urlopen
|      |      +--urllib.request.urlopen
|      |      +--twitter.api.TwitterHTTPError.__init__
|      |      |      +--io.BytesIO
|      |      |      +--cStringIO.StringIO
|      |      |      +--gzip.GzipFile
|      |      |      +--simplejson.loads
|      |      |      +--json.loads
|      |      +--twitter.stream.TwitterJSONIter.__init__
|      +--twitter.api.TwitterCall.__init__
+--twitter.oauth.OAuth.__init__
|      +--twitter.auth.MissingCredentialsError.__init__
+--twitter.api.TwitterHTTPError.__init__
+--twitter.api.Twitter.__init__
|      +--twitter.auth.NoAuth.__init__
|      +--twitter.api.TwitterCall.__init__

We scan twitter's versions and observe that during its evolution between any version from [1.18.0] and 1.17.1, the changing functions (diffs being listed below) have none intersection with any function or API we mentioned above (either directly or indirectly called by this project).

diff: 1.17.1(original) 1.18.0
['twitter.api.TwitterCall.__call__', 'twitter.stream.TwitterJSONIter.__iter__', 'twitter.api.TwitterCall._handle_response_with_retry', 'twitter.cmdline.SetStatusAction.__call__', 'twitter.oauth_dance.oauth2_dance', 'twitter.oauth2.read_bearer_token_file', 'twitter.cmdline.UserAction', 'twitter.stream_example.parse_arguments', 'twitter.oauth_dance.oauth_dance', 'twitter.stream_example.main', 'twitter.api.Twitter', 'twitter.stream.TwitterJSONIter', 'twitter.oauth_dance.get_oauth_pin', 'twitter.cmdline.UserAction.getStatuses', 'twitter.cmdline.SetStatusAction', 'twitter.api.TwitterCall']

As for other packages, the APIs of io, cStringIO, gzip, simplejson, json, urllib2 and urllib are called by twitter in the call graph and the dependencies on these packages also stay the same in our suggested versions, thus avoiding any outside conflict.

Therefore, we believe that it is quite safe to loose your dependency on twitter from "twitter==1.17.1" to "twitter>=1.17.1,<=1.18.0". This will improve the applicability of chirps and reduce the possibility of any further dependency conflict with other projects.