Properly handle non-200 responses on multi-url requests

[dougkeen]

Currently, multi-url requests throw a ValueError when constructing the return list if the api requests returns anything other than a 200 response. The error happens specifically in this code:

return map(lambda url, data: Url(data, method, url),
                        url_or_urls, data)

When the status code isn't 200 (and it's a multi-url request), the data value is assigned to a dictionary (as opposed the list/json array you'd expect from a 200 response). When passed to map(lambda url, data: Url(data, method, url), url_or_urls, data), map iterates through data and url_or_urls in parallel. Under successful 200 responses, data and url_or_urls are lists of equal length. In any other case, data is a dictionary, so map iterates through the keys of the dictionary. This causes exceptions because the data arg passed to the lambda func is now a string, not a dict.

This fix works by simply copying the error data len(url_or_urls) times in a list, mimicking the list format expected in the downstream map function.