Python Forum

Hello,

We have an app that provides a list of searchable multi-layered items originally written in 2.7 and we're converting to 3.8.2. It is hosted on Heroku and is backed by a git repo for those items it displays on its pages.

I have followed the future package tutorial found here https://python-future.org/automatic_conversion.html and have worked through all dependency work.

I have appended 'b' to those elements that were originally referenced as binary-strings in 2.7 and which are need to now be explicitly stated.

I am now caught at sections.sort() line 26 :

def get_sections():
    sections = []
    for path,dirs,files in os.walk(folder):
        print("path: {} dir: {} ".format(path, dirs))
        dirs[:] = [d for d in dirs if not d[0] ==  '.' ]


        for filename in files:

            #   section folder
            if filename.lower() == "readme.md" and len(dirs) != 0 and path != folder:
                #   print os.path.join(path,filename)
                pth = os.path.join(re.sub(folder, '', path), filename)
                pth = pth.lstrip('/')
                with open(os.path.join(path,filename), 'rb') as readme:
                    description = readme.read()
                    description = description.replace(b"##", b"")
                    section_name = path.split(os.path.sep)[-1]
                    section = {
                        "name": section_name,
                        "description": description,
                        "slug": urllib.parse.quote(section_name),
                        "examples": []
                    }
                    sections.append(section)
    sections.sort()
    return sections

The error I get is "TypeError: '<' not supported between instances of 'dict' and 'dict'"

Since finding out Python 3 doesn't support sorting dicts the same way Python 2 does I changed it to
sections = {k: disordered[k] for k in sorted(sections)}

and still get "TypeError: '<' not supported between instances of 'dict' and 'dict'"

Any general guidance on what is happening between the dictionaries I'm creating and sorting would be much appreciated.

Funny, I even did not know that you can't do that.
But there is a solution. You can use the key-function to convert
the keys to a tuple or list. Then this object is used for comparison.

sorted([{-21: None, 2: None}, {-100: None, -2: None}], key=lambda x: tuple(x.keys()))

The key-function can also written as normal function:

def dict_sort(mapping):
    return tuple(mapping.keys())

sorted([{-21: None, 2: None}, {-100: None, -2: None}], key=dict_sort)

You can also choose a key, which you want to use for sorting or you can select values to sort the dict.
It depends on what you want to reach.

Thank you DeaD_EyE.

I appreciate the full response and the function inclusion!