code: def dictionary(value):
      
      if not value:
          return {}
      value = value.replace('logscale(', '("logscale", ')  # dirty but quick
      try:
          dic = dict(ast.literal_eval(value))
      except Exception:
          raise ValueError('%r is not a valid Python dictionary' % value)
      for key, val in dic.items():
          try:
              has_logscale = (val[0] == 'logscale')
          except Exception:  # no val[0]
              continue
          if has_logscale:
              dic[key] = list(logscale(*val[1:]))
      return dic
docs: :param value:
          input string corresponding to a literal Python object
      :returns:
          the Python object
  
      >>> dictionary('')
      {}
      >>> dictionary('{}')
      {}
      >>> dictionary('{"a": 1}')
      {'a': 1}
      >>> dictionary('"vs30_clustering: true"')  # an error really done by a user
      Traceback (most recent call last):
         ...
      ValueError: '"vs30_clustering: true"' is not a valid Python dictionary
      >>> dictionary('{"ls": logscale(0.01, 2, 5)}')
      {'ls': [0.01, 0.03760603093086393, 0.14142135623730948, 0.5318295896944986, 1.9999999999999991]}