Issue #16828: Fix error incorrectly raised by bz2.compress(b'') and bz2.BZ2Compressor...

Initial patch by Martin Packman.

diff --cc Lib/test/test_bz2.py
index fb2f78288634ff85ceac6e6e7d3a2925d458b5dc,912fac1c3344f4359ddb81d9af333148a2c9ed5e..8703df7909fd5eb86d31e7be2f607a94f1ec7199
--- 1/Lib/test/test_bz2.py
--- 2/Lib/test/test_bz2.py
+++ b/Lib/test/test_bz2.py
@@@ -47,9 -47,10 +47,10 @@@ class BaseTest(unittest.TestCase)
          ]
      TEXT = b''.join(TEXT_LINES)
      DATA = b'BZh91AY&SY.\xc8N\x18\x00\x01>_\x80\x00\x10@\x02\xff\xf0\x01\x07n\x00?\xe7\xff\xe00\x01\x99\xaa\x00\xc0\x03F\x86\x8c#&\x83F\x9a\x03\x06\xa6\xd0\xa6\x93M\x0fQ\xa7\xa8\x06\x804hh\x12$\x11\xa4i4\xf14S\xd2<Q\xb5\x0fH\xd3\xd4\xdd\xd5\x87\xbb\xf8\x94\r\x8f\xafI\x12\xe1\xc9\xf8/E\x00pu\x89\x12]\xc9\xbbDL\nQ\x0e\t1\x12\xdf\xa0\xc0\x97\xac2O9\x89\x13\x94\x0e\x1c7\x0ed\x95I\x0c\xaaJ\xa4\x18L\x10\x05#\x9c\xaf\xba\xbc/\x97\x8a#C\xc8\xe1\x8cW\xf9\xe2\xd0\xd6M\xa7\x8bXa<e\x84t\xcbL\xb3\xa7\xd9\xcd\xd1\xcb\x84.\xaf\xb3\xab\xab\xad`n}\xa0lh\tE,\x8eZ\x15\x17VH>\x88\xe5\xcd9gd6\x0b\n\xe9\x9b\xd5\x8a\x99\xf7\x08.K\x8ev\xfb\xf7xw\xbb\xdf\xa1\x92\xf1\xdd|/";\xa2\xba\x9f\xd5\xb1#A\xb6\xf6\xb3o\xc9\xc5y\\\xebO\xe7\x85\x9a\xbc\xb6f8\x952\xd5\xd7"%\x89>V,\xf7\xa6z\xe2\x9f\xa3\xdf\x11\x11"\xd6E)I\xa9\x13^\xca\xf3r\xd0\x03U\x922\xf26\xec\xb6\xed\x8b\xc3U\x13\x9d\xc5\x170\xa4\xfa^\x92\xacDF\x8a\x97\xd6\x19\xfe\xdd\xb8\xbd\x1a\x9a\x19\xa3\x80ankR\x8b\xe5\xd83]\xa9\xc6\x08\x82f\xf6\xb9"6l$\xb8j@\xc0\x8a\xb0l1..\xbak\x83ls\x15\xbc\xf4\xc1\x13\xbe\xf8E\xb8\x9d\r\xa8\x9dk\x84\xd3n\xfa\xacQ\x07\xb1%y\xaav\xb4\x08\xe0z\x1b\x16\xf5\x04\xe9\xcc\xb9\x08z\x1en7.G\xfc]\xc9\x14\xe1B@\xbb!8`'
+     EMPTY_DATA = b'BZh9\x17rE8P\x90\x00\x00\x00\x00'
  
      def setUp(self):
 -        self.filename = TESTFN
 +        self.filename = support.TESTFN
  
      def tearDown(self):
          if os.path.isfile(self.filename):

diff --cc Misc/ACKS
Simple merge

diff --cc Misc/NEWS
index eaa8cfc30dcdfa55e5657813e78c59cad3d8dc64,5a9e1aea3516cbeed9884c4166deb2a5e066531b..9e629e416431d4a48a7bda4f20e788d784053c63
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -199,10 -123,9 +199,13 @@@ Core and Builtin
  Library
  -------
  
+ - Issue #16828: Fix error incorrectly raised by bz2.compress(b'') and
+   bz2.BZ2Compressor.compress(b''). Initial patch by Martin Packman.
+ 
 +- Issue #16833: In http.client.HTTPConnection, do not concatenate the request
 +  headers and body when the payload exceeds 16 KB, since it can consume more
 +  memory for no benefit.  Patch by Benno Leslie.
 +
  - Issue #16541: tk_setPalette() now works with keyword arguments.
  
  - Issue #16820: In configparser, `parser.popitem()` no longer raises ValueError.