how to return streams

strava_streams_api.py

### CURRENT

# Result is a enum of streams in any order. To get a particular stream you loop through them,
#  and ask for it's type.  A particular requested stream is not returned if it's not
#  on the activity (need to code defensively).

streams = client.get_activity_streams(123, types=types, resolution='medium')

heartrate_stream = None
for s in streams:
    if s.type == 'heartrate':
        heartrate_stream = s
        break

if heartrate_stream is not None:
    # do something 
    max(heartrate_stream.data)


### PROPOSED
# Instead of an enum, the get_activity_streams could return a dictionary type object.
#  Put the type as the dict's key name.

streams = client.get_activity_streams(123, types=types, resolution='medium')

if 'heartrate' in streams.keys():
    # do something
    max(streams['heartrate'].data)

Yeah, that seems like a useful improvement. I wonder if we should keep an option (e.g. optional param) for the current implementation -- or perhaps make a get_activity_stream_dict that returns a dict instead of a list. In the end, though, I think modifying the current function as long as api docs are updated to reflect new return type/structure, should be just fine.