Error while installing gitsome

Error

 installing to build/bdist.macosx-10.6-intel/wheel
  running install
  Remove xonsh/parser_table.py
  Building lexer and parser tables.
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
    File "/private/tmp/pip-build-xizu34ed/gitsome/setup.py", line 129, in <module>
      main()
    File "/private/tmp/pip-build-xizu34ed/gitsome/setup.py", line 122, in main
      setup(**skw)
    File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/core.py", line 148, in setup
      dist.run_commands()
    File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/dist.py", line 955, in run_commands
      self.run_command(cmd)
    File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/dist.py", line 974, in run_command
      cmd_obj.run()
    File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/wheel/bdist_wheel.py", line 215, in run
      self.run_command('install')
    File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/dist.py", line 974, in run_command
      cmd_obj.run()
    File "/private/tmp/pip-build-xizu34ed/gitsome/setup.py", line 44, in run
      build_tables()
    File "/private/tmp/pip-build-xizu34ed/gitsome/setup.py", line 37, in build_tables
      outputdir='xonsh')
    File "/private/tmp/pip-build-xizu34ed/gitsome/xonsh/parser.py", line 233, in __init__
      self.parser = yacc.yacc(**yacc_kwargs)
    File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/ply/yacc.py", line 3403, in yacc
      raise YaccError('Unable to build parser')
  ply.yacc.YaccError: Unable to build parser
  
  ----------------------------------------
  Failed building wheel for gitsome
  Running setup.py clean for gitsome
Failed to build gitsome
Installing collected packages: gitsome
  Running setup.py install for gitsome ... error
    Complete output from command /Library/Frameworks/Python.framework/Versions/3.6/bin/python3 -u -c "import setuptools, tokenize;__file__='/private/tmp/pip-build-xizu34ed/gitsome/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-5z97gk4c-record/install-record.txt --single-version-externally-managed --compile:
    
    running install
    Building lexer and parser tables.
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/private/tmp/pip-build-xizu34ed/gitsome/setup.py", line 129, in <module>
        main()
      File "/private/tmp/pip-build-xizu34ed/gitsome/setup.py", line 122, in main
        setup(**skw)
      File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/core.py", line 148, in setup
        dist.run_commands()
      File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/dist.py", line 955, in run_commands
        self.run_command(cmd)
      File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/dist.py", line 974, in run_command
        cmd_obj.run()
      File "/private/tmp/pip-build-xizu34ed/gitsome/setup.py", line 44, in run
        build_tables()
      File "/private/tmp/pip-build-xizu34ed/gitsome/setup.py", line 37, in build_tables
        outputdir='xonsh')
      File "/private/tmp/pip-build-xizu34ed/gitsome/xonsh/parser.py", line 233, in __init__
        self.parser = yacc.yacc(**yacc_kwargs)
      File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/ply/yacc.py", line 3403, in yacc
        raise YaccError('Unable to build parser')
    ply.yacc.YaccError: Unable to build parser
    
    ----------------------------------------
Command "/Library/Frameworks/Python.framework/Versions/3.6/bin/python3 -u -c "import setuptools, tokenize;__file__='/private/tmp/pip-build-xizu34ed/gitsome/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-5z97gk4c-record/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /private/tmp/pip-build-xizu34ed/gitsome/