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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def parseWigString(line, scoreType=int):
 """ Parse a string in simple Wig format and return a GenomicInterval. :param line: the string to be parsed :param scoreType: treat the score field as having this type. :return: GenomicInterval object representing this wig line; the name of the interval will be set to 'X', and it's strand to the default. """

  parts = line.split("\t")
  if (len(parts) < 4):
    raise GenomicIntervalError("failed to parse " + line +
                               " as wig format, too few fields")
  return GenomicInterval(parts[0].strip(), int(parts[1]), int(parts[2]), None,
                         scoreType(parts[3]))