code: def from_string(self, value):
          
          # Remove optional {}
          if value.startswith('{') and value.endswith('}'):
              text = value[1:-1].strip()
          else:
              text = value.strip()
          # Result is a dictionary
          result = {}
          # Convert each pair of <int>:<float> into a key, value pair.
          for val in text.split(','):
              tokens = val.split(':')
              if len(tokens) != 2:
                  raise ValueError('invalid entry in dictionary: ' + val)
              result[str(int(tokens[0].strip()))] = float(tokens[1].strip())
          return result
docs: Convert string to dictionary.