code: def clean(ctx):
      
      os.chdir(PROJECT_DIR)
      patterns = ['.cache',
                  '.coverage',
                  '.eggs',
                  'build',
                  'dist']
      ctx.run('rm -vrf {0}'.format(' '.join(patterns)))
      ctx.run('''find . \( -name '*,cover' -o -name '__pycache__' -o -name '*.py[co]' -o -name '_work' \) '''
              '''-exec rm -vrf '{}' \; || true''')
docs: clean generated project files