code: def get_vcf_header(source):
      
      head = HeaderParser()
      #Parse the header lines
      for line in source:
          line = line.rstrip()
          if line.startswith('#'):
              if line.startswith('##'):
                  logger.debug("Found metadata line {0}".format(line))
                  head.parse_meta_data(line)
              else:
                  logger.debug("Found header line {0}".format(line))
                  head.parse_header_line(line)
          else:
              break
      
      return head
docs: Get the header lines of a vcf file
      
          Args:
              source(iterable): A vcf file
          
          Returns:
              head (HeaderParser): A headerparser object