code: def load_bim(self, map3=False):
          
          cols = [0, 1, 3, 4, 5]
          if map3:
              cols = [0, 1, 2, 3, 4]
          logging.info("Loading file: %s" % self.bim_file)
          val = sys_call('wc -l %s' % (self.bim_file))[0][0].split()[0]
          marker_count = int(val)
          self.markers = numpy.zeros((marker_count, 2), dtype=int)
          self.rsids = []
          self.alleles = []
  
          with open(self.bim_file) as file:
              index = 0
              for line in file:
                  if map3:
                      chr, rsid, pos, al1, al2 = line.strip().split()
                  else:
                      chr, rsid, gd, pos, al1, al2 = line.strip().split()
                  self.markers[index, 0] = int(chr)
                  self.markers[index, 1] = int(pos)
                  self.alleles.append([al1, al2])
                  self.rsids.append(rsid)
                  index += 1
          self.locus_count = self.markers.shape[0]
docs: Basic marker details loading.
  
              (chr, rsid, gen. dist, pos, allelel 1, allele2)
  
          :param map3: When true, ignore the genetic distance column
          :return: None