class_docstr: Reads/writes `RecordIO` data format, supporting random access.
  
  Examples
  ---------
  >>> for i in range(5):
  ...     record.write_idx(i, 'record_%d'%i)
  >>> record.close()
  >>> record = mx.recordio.MXIndexedRecordIO('tmp.idx', 'tmp.rec', 'r')
  >>> record.read_idx(3)
  record_3
  
  Parameters
  ----------
  idx_path : str
      Path to the index file.
  uri : str
      Path to the record file. Only supports seekable file types.
  flag : str
      'w' for write or 'r' for read.
  key_type : type
      Data type for keys.
docstr: Sets the current read pointer position.
  
  This function is internally called by `read_idx(idx)` to find the current
  reader pointer position. It doesn't return anything.
docstr_tok: ["Sets","the","current","read","pointer","position",".","This","function","is","internally","called","by","`","read_idx","(","idx",")","`","to","find","the","current","reader","pointer","position",".","It","does","n't","return","anything","."]
code: def seek(self, idx):
      """Sets the current read pointer position.
  
      This function is internally called by `read_idx(idx)` to find the current
      reader pointer position. It doesn't return anything."""
      assert not self.writable
      self._check_pid(allow_reset=True)
      pos = ctypes.c_size_t(self.idx[idx])
      check_call(_LIB.MXRecordIOReaderSeek(self.handle, pos))
  
imports: from collections import namedtuple
  from multiprocessing import current_process
  import ctypes
  import struct
  import numbers
  import numpy
  from .base import _LIB
  from .base import RecordIOHandle
  from .base import check_call
  from .base import c_str
label_desc: Use image node_id 5 for calling the MXIndexedRecordIO obj's underlying member method code with example usage: obj.seek(idx) without return types