code: def parse_number(d, key, regex, s):
      
      result = find_number(regex, s)
      if result is not None:
          d[key] = result
docs: Find a number using a given regular expression.
      If the number is found, sets it under the key in the given dictionary.
      
      d - The dictionary that will contain the data.
      key - The key into the dictionary.
      regex - A string containing the regular expression.
      s - The string to search.