Python 3 compatibility issues

[cclauss]

Python 2 end of life is in less than 200 days...

flake8 testing of https://github.com/SlavikMIPT/tgcloud on Python 3.7.1

$ flake8 . --count --select=E9,F63,F72,F82 --show-source --statistics

./dedupfs/get_memory_usage.py:42:13: E999 SyntaxError: invalid syntax
    print msg % (format_size(counter), format_size(new_memory_usage), format_size(difference), format_size(deviation))
            ^
./dedupfs/fuse.py:59:34: E999 SyntaxError: invalid syntax
                           (var, `pattern`))
                                 ^
./dedupfs/dedupfs.py:49:19: E999 SyntaxError: invalid syntax
except ImportError, e:
                  ^
3     E999 SyntaxError: invalid syntax
3

E901,E999,F821,F822,F823 are the "showstopper" flake8 issues that can halt the runtime with a SyntaxError, NameError, etc. These 5 are different from most other flake8 issues which are merely "style violations" -- useful for readability but they do not effect runtime safety.

• F821: undefined name name
• F822: undefined name name in __all__
• F823: local variable name referenced before assignment
• E901: SyntaxError or IndentationError
• E999: SyntaxError -- failed to compile a file into an Abstract Syntax Tree

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[VadVergasov]

Run this threw python2, as it showed on https://habr.com/en/company/vds/blog/456290/ you need to run

python3.6 download_service.py

with python 3, but

python dedupfs/dedupfs.py --block-size 10240000 storage/

with python 2. Also, download_service.py have the first line, which shows that it is python3, but dedupfs have python 2.
Hope it helped.