Key error articles() pset8

Question

When I try to test my /articles route with the postal code 02138 (or any other code for that matter) I get something along the lines of this:

KeyError: '02138' at line 43:

cache = lookup(str(coordinates))

articles function:

@app.route("/articles")
def articles():
"""Look up articles for geo."""

# cannot use try here unfortunately
if not request.args.get("geo"):
    raise RuntimeError("invalid lat/lng")

coordinates = request.args.get("geo")

# now use lookup (in helpers.py) to return newsfeed
cache = lookup(str(coordinates)) 

return jsonify([cache])

If I didn't know better, I would have thought the error would be with jsonify since I don't know if I entirely understand how it works (I found flask's documentation to be a little cryptic on it), but instead it is this line.

The reason I cast coordinates to a string was to make sure that they are not numeric as per dino's answer here:

pset8 addMarker can't get articles

EDIT

I changed the last line of my code to be

return jsonify(cache)

Based on some answers I read from Dino, but since the problem is with the line previous, it hasn't really fixed anything.

Here is the traceback error:

Traceback (most recent call last):
  File "/usr/local/lib/python3.4/dist-packages/flask/app.py", line 1994, in 
__call__
    return self.wsgi_app(environ, start_response)
  File "/usr/local/lib/python3.4/dist-packages/flask/app.py", line 1985, in 
wsgi_app
    response = self.handle_exception(e)
  File "/usr/local/lib/python3.4/dist-packages/flask/app.py", line 1540, in 
handle_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python3.4/dist-packages/flask/_compat.py", line 33, 
in reraise
    raise value
  File "/usr/local/lib/python3.4/dist-packages/flask/app.py", line 1982, in 
wsgi_app
    response = self.full_dispatch_request()
  File "/usr/local/lib/python3.4/dist-packages/flask/app.py", line 1614, in 
full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/usr/local/lib/python3.4/dist-packages/flask/app.py", line 1517, in 
handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python3.4/dist-packages/flask/_compat.py", line 33, 
in reraise
    raise value
  File "/usr/local/lib/python3.4/dist-packages/flask/app.py", line 1612, in 
full_dispatch_request
    rv = self.dispatch_request()
  File "/usr/local/lib/python3.4/dist-packages/flask/app.py", line 1598, in 
dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/ubuntu/workspace/pset8/mashup/application.py", line 43, in 
articles
    cache = lookup(str(coordinates))
  File "/home/ubuntu/workspace/pset8/mashup/helpers.py", line 9, in lookup
    return lookup.cache[geo]
KeyError: '02138'

Answer 1

There's a "problem" in the distro code. I just downloaded it and compared it to my (working) version, which was downloaded.... some time back. Line 8 needs to be uncommented, and line 9 needs to be properly indented. Like so:

# check cache for geo <-- LINE 7
if geo in lookup.cache:
    return lookup.cache[geo]

That appears to be the only difference between the codes.