python 3.10 removes parser

[krsna1729]

Traceback (most recent call last):
  File "/opt/bess/bessctl/./bessctl", line 42, in <module>
    import commands
  File "/opt/bess/bessctl/commands.py", line 52, in <module>
    import sugar
  File "/opt/bess/bessctl/sugar.py", line 34, in <module>
    import parser
ModuleNotFoundError: No module named 'parser'

https://docs.python.org/3/library/parser.html

Removed the parser module, which was deprecated in 3.9 due to the switch to the new PEG parser, as well as all the C source and header files that were only being used by the old parser, including node.h, parser.h, graminit.h and grammar.h.

https://docs.python.org/3.10/whatsnew/3.10.html#removed

[krsna1729]

#347 (comment)