def METHOD_NAME():
  file_iter = open(op.join(
    extract_from_symmetry_lib.ccp4io_lib_data, "symop.lib"))
  ccp4_id_counts = libtbx.dict_with_default_0()
  ccp4_symbol_counts = libtbx.dict_with_default_0()
  for line in file_iter:
    flds = line.split(None, 4)
    ccp4_id = flds[0]
    ccp4_id_counts[ccp4_id] += 1
    space_group_number = int(ccp4_id[-3:])
    order_z = int(flds[1])
    given_ccp4_symbol = flds[3]
    ccp4_symbol_counts[given_ccp4_symbol] += 1
    group = extract_from_symmetry_lib.collect_symops(
      file_iter=file_iter, order_z=order_z)
    assert group.order_z() == order_z
    space_group_info = sgtbx.space_group_info(group=group)
    retrieved_ccp4_symbol = extract_from_symmetry_lib.ccp4_symbol(
      space_group_info=space_group_info,
      lib_name="symop.lib")
    assert retrieved_ccp4_symbol == given_ccp4_symbol
    assert space_group_info.type().number() == space_group_number
    if (1):
      from iotbx.pdb import format_cryst1_sgroup
      sgroup = format_cryst1_sgroup(space_group_info=space_group_info)
      if (len(sgroup) > 11):
        print("ccp4 symop.lib setting leads to pdb CRYST1 overflow:",\
          ccp4_id, given_ccp4_symbol, sgroup)
  file_iter.close()
  for ccp4_id,count in ccp4_id_counts.items():
    if (count != 1):
      raise RuntimeError(
        'ccp4 id "%s" appears %d times (should be unique).'
          % (ccp4_id, count))
  ccp4_symbol_counts = libtbx.dict_with_default_0()
  for ccp4_symbol,count in ccp4_symbol_counts.items():
    if (count != 1):
      raise RuntimeError(
        'ccp4 symbol "%s" appears %d times (should be unique).'
          % (ccp4_symbol, count))