# Copyright 2015 Google Inc. All Rights Reserved.
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# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
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# http://www.apache.org/licenses/LICENSE-2.0
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"""## Data IO (Python Functions)
A TFRecords file represents a sequence of (binary) strings. The format is not
random access, so it is suitable for streaming large amounts of data but not
suitable if fast sharding or other non-sequential access is desired.
@@TFRecordWriter
@@tf_record_iterator
- - -
### TFRecords Format Details
A TFRecords file contains a sequence of strings with CRC hashes. Each record
has the format
uint64 length
uint32 masked_crc32_of_length
byte data[length]
uint32 masked_crc32_of_data
and the records are concatenated together to produce the file. The CRC32s
are [described here](https://en.wikipedia.org/wiki/Cyclic_redundancy_check),
and the mask of a CRC is
masked_crc = ((crc >> 15) | (crc << 17)) + 0xa282ead8ul
"""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from tensorflow.python.lib.io.tf_record import *