PYTHON-686 - Finish updating docs related to python 3.

Mostly removing references to 2to3, which we no longer use.

CONTRIBUTING.rst

@@ -19,13 +19,8 @@ that might not be of interest or that has already been addressed.
 Supported Interpreters
 ----------------------
 
-PyMongo supports CPython 2.4 and newer, PyPy, and Jython. Language
-features not supported by all interpreters can not be used (e.g.
-the `with statement
-<http://docs.python.org/reference/compound_stmts.html#the-with-statement>`_
-is not supported in Python 2.4). Please also ensure that your code is
-properly converted by `2to3 <http://docs.python.org/library/2to3.html>`_ for
-Python 3 support.
+PyMongo supports CPython 2.6, 2.7, 3.2 and newer, and PyPy. Language
+features not supported by all interpreters can not be used.
 
 Style Guide
 -----------

bson/__init__.py

@@ -278,9 +278,8 @@ def _get_timestamp(
 
 
 def _get_long(data, position, as_class, tz_aware, uuid_subtype, compile_re):
-    # Have to cast to long; on 32-bit unpack may return an int.
-    # 2to3 will change long to int. That's fine since long doesn't
-    # exist in python3.
+    # Have to cast to long (for python 2.x); on 32-bit unpack may return
+    # an int.
     value = long(struct.unpack("<q", data[position:position + 8])[0])
     position += 8
     return value, position
@@ -304,7 +303,7 @@ _element_getter = {
     BSONCWS: _get_code_w_scope,
     BSONINT: _get_int,  # number_int
     BSONTIM: _get_timestamp,
-    BSONLON: _get_long, # Same as _get_int after 2to3 runs.
+    BSONLON: _get_long,
     BSONMIN: lambda u, v, w, x, y, z: (MinKey(), v),
     BSONMAX: lambda u, v, w, x, y, z: (MaxKey(), v)}
 
@@ -424,8 +423,6 @@ def _element_to_bson(key, value, check_keys, uuid_subtype):
         if value > MAX_INT32 or value < MIN_INT32:
             return BSONLON + name + struct.pack("<q", value)
         return BSONINT + name + struct.pack("<i", value)
-    # 2to3 will convert long to int here since there is no long in python3.
-    # That's OK. The previous if block will match instead.
     if not PY3 and isinstance(value, long):
         if value > MAX_INT64 or value < MIN_INT64:
             raise OverflowError("BSON can only handle up to 8-byte ints")

doc/python3.rst

@@ -134,39 +134,3 @@ version older than 3.2.3::
   ObjectId('5b37392c203135302c203234362c2034352c203235312c203136352c2033342c203532...')
 
 
-Why do I get a syntax error importing pymongo after installing from source?
----------------------------------------------------------------------------
-
-PyMongo makes use of the 2to3 tool to translate much of its code to valid
-Python 3 syntax at install time. The translated modules are written to the
-build subdirectory before being installed, leaving the original source files
-intact. If you start the python interactive shell from the top level source
-directory after running ``python setup.py install`` the untranslated modules
-will be the first thing in your path. Importing pymongo will result in an
-exception similar to::
-
-  Python 3.2.5 (default, Feb 26 2014, 12:40:25)
-  [GCC 4.7.3] on linux2
-  Type "help", "copyright", "credits" or "license" for more information.
-  >>> import pymongo
-  Traceback (most recent call last):
-    File "<stdin>", line 1, in <module>
-    File "pymongo/__init__.py", line 77, in <module>
-      version = get_version_string()
-    File "pymongo/__init__.py", line 73, in get_version_string
-      if isinstance(version_tuple[-1], basestring):
-  NameError: global name 'basestring' is not defined
-
-Note the path in the traceback (``pymongo/__init__.py``). Changing out of the
-source directory takes the untranslated modules out of your path::
-
-  $ cd ..
-  $ python
-  Python 3.2.5 (default, Feb 26 2014, 12:40:25)
-  [GCC 4.7.3] on linux2
-  Type "help", "copyright", "credits" or "license" for more information.
-  >>> import pymongo
-  >>> pymongo.__file__
-  '/home/behackett/py3k/lib/python3.2/site-packages/pymongo-2.7-py3.2-linux-x86_64.egg/pymongo/__init__.py'
-
-

pymongo/collection.py

@@ -1022,7 +1022,7 @@ class Collection(common.BaseObject):
             warnings.warn("ttl is deprecated. Please use cache_for instead.",
                           DeprecationWarning, stacklevel=2)
 
-        # The types supported by datetime.timedelta. 2to3 removes long.
+        # The types supported by datetime.timedelta.
         if not (isinstance(cache_for, integer_types) or
                 isinstance(cache_for, float)):
             raise TypeError("cache_for must be an integer or float.")

test/test_gridfs.py

@@ -384,7 +384,6 @@ class TestGridfs(unittest.TestCase):
         self.assertEqual(3, self.fs.find({"filename":"two"}).count())
         self.assertEqual(4, self.fs.find().count())
         cursor = self.fs.find(timeout=False).sort("uploadDate", -1).skip(1).limit(2)
-        # 2to3 hint...
         gout = next(cursor)
         self.assertEqual(b"test1", gout.read())
         cursor.rewind()