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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 parse_line(self, line):
 """ For each line we are passed, call the XML parser. Returns the line if we are outside one of the ignored tables, otherwise returns the empty string. @param line: the line of the LIGO_LW XML file to be parsed @type line: string @return: the line of XML passed in or the null string @rtype: string """

    self.__p.Parse(line)
    if self.__in_table:
      self.__silent = 1
    if not self.__silent:
      ret = line
    else:
      ret = ""
    if not self.__in_table:
      self.__silent = 0
    return ret