NetworkBase fetch() and fetch_data() headers param listed as wrong type

[zsimpso]

In working on a project and reading the docs for PortalBase.network I ran into a lot of confusion seeing that fetch() has headers as a list type[0].

Seeings how header params are nearly always a dictionary I decided to pass a dictionary and it worked. Also, from what I understand the underlying adafruit_requests is based on they Python Requests library, which also uses a dictionary for headers params[1].

When I try and pass a list I encounter the following traceback:

  File "code.py", line 34, in <module>
  File "code.py", line 30, in fetch_data
  File "adafruit_portalbase/network.py", line 548, in fetch_data
  File "adafruit_portalbase/network.py", line 467, in fetch
  File "adafruit_requests.py", line 684, in get
  File "adafruit_requests.py", line 567, in request
  File "adafruit_requests.py", line 565, in request
  File "adafruit_requests.py", line 494, in _send_request
  TypeError: list indices must be integers, not str

Looking into adafruit_requests it does indeed look to expect a dict[2].

[0] https://github.com/adafruit/Adafruit_CircuitPython_PortalBase/blob/main/adafruit_portalbase/network.py#L450
[1] https://docs.python-requests.org/en/master/user/quickstart/#custom-headers
[2] https://github.com/adafruit/Adafruit_CircuitPython_Requests/blob/master/adafruit_requests.py#L533