code: def readMAP(fileName, prefix):
      
      # Saving the MAP file
      mapF = None
      with open(fileName, 'r') as inputFile:
          mapF = [
              tuple(i.rstrip("\r\n").split("\t")) for i in inputFile.readlines()
          ]
  
      # Test for uniqueness of names
      marker_names = np.array([i[1] for i in mapF])
      nb_with_same_name = len(marker_names) - len(np.unique(marker_names))
      if nb_with_same_name > 0:
          logger.info("  - {} markers with same name".format(nb_with_same_name))
          u, indices = np.unique(marker_names, return_index=True)
          duplicated_indices = np.setdiff1d(np.arange(len(marker_names)),
                                            indices)
          duplicated_indices = np.in1d(marker_names,
                                       marker_names[duplicated_indices])
          marker_chr_pos = np.array([(i[0], i[3]) for i in mapF],
                                    dtype=[("chr", int),
                                           ("pos", int)])[duplicated_indices]
          marker_names = marker_names[duplicated_indices]
          try:
              duplicated_marker_names = open(prefix + ".duplicated_marker_names",
                                             "w")
          except IOError:
              msg = "{}.duplicated_marker_names: can't write file".format(prefix)
              raise ProgramError(msg)
          for i in xrange(len(marker_names)):
              print >>duplicated_marker_names, "\t".join([marker_names[i]] +
                                                         map(str,
                                                             marker_chr_pos[i]))
          duplicated_marker_names.close()
  
      return mapF
docs: Reads the MAP file.
  
      :param fileName: the name of the ``map`` file.
  
      :type fileName: str
  
      :returns: a list of tuples, representing the ``map`` file.
  
      While reading the ``map`` file, it saves a file
      (``prefix.duplicated_marker_names``) containing the name of the unique
      duplicated markers.