(cleanup) remove Python 2 remaining items

cassandra/cluster.py

@@ -16,7 +16,6 @@
 This module houses the main classes you will interact with,
 :class:`.Cluster` and :class:`.Session`.
 """
-from __future__ import absolute_import
 
 import atexit
 import datetime
@@ -110,10 +109,7 @@
     # TODO: remove it when eventlet issue would be fixed
     EventletConnection = None
 
-try:
-    from weakref import WeakSet
-except ImportError:
-    from cassandra.util import WeakSet  # NOQA
+from weakref import WeakSet
 
 def _is_gevent_monkey_patched():
     if 'gevent.monkey' not in sys.modules:
@@ -183,12 +179,6 @@ def _connection_reduce_fn(val,import_fn):
     raise DependencyException("Exception loading connection class dependencies", excs)
 DefaultConnection = conn_class
 
-# Forces load of utf8 encoding module to avoid deadlock that occurs
-# if code that is being imported tries to import the module in a seperate
-# thread.
-# See http://bugs.python.org/issue10923
-"".encode('utf8')
-
 log = logging.getLogger(__name__)
 
 
@@ -1548,34 +1538,33 @@ def _create_thread_pool_executor(self, **kwargs):
         Create a ThreadPoolExecutor for the cluster. In most cases, the built-in
         `concurrent.futures.ThreadPoolExecutor` is used.
 
-        Python 3.7+ and Eventlet cause the `concurrent.futures.ThreadPoolExecutor`
+        Eventlet causes the `concurrent.futures.ThreadPoolExecutor`
         to hang indefinitely. In that case, the user needs to have the `futurist`
         package so we can use the `futurist.GreenThreadPoolExecutor` class instead.
 
         :param kwargs: All keyword args are passed to the ThreadPoolExecutor constructor.
         :return: A ThreadPoolExecutor instance.
         """
         tpe_class = ThreadPoolExecutor
-        if sys.version_info[0] >= 3 and sys.version_info[1] >= 7:
-            try:
-                from cassandra.io.eventletreactor import EventletConnection
-                is_eventlet = issubclass(self.connection_class, EventletConnection)
-            except:
-                # Eventlet is not available or can't be detected
-                return tpe_class(**kwargs)
+        try:
+            from cassandra.io.eventletreactor import EventletConnection
+            is_eventlet = issubclass(self.connection_class, EventletConnection)
+        except:
+            # Eventlet is not available or can't be detected
+            return tpe_class(**kwargs)
 
-            if is_eventlet:
-                try:
-                    from futurist import GreenThreadPoolExecutor
-                    tpe_class = GreenThreadPoolExecutor
-                except ImportError:
-                    # futurist is not available
-                    raise ImportError(
-                        ("Python 3.7+ and Eventlet cause the `concurrent.futures.ThreadPoolExecutor` "
-                         "to hang indefinitely. If you want to use the Eventlet reactor, you "
-                         "need to install the `futurist` package to allow the driver to use "
-                         "the GreenThreadPoolExecutor. See https://github.com/eventlet/eventlet/issues/508 "
-                         "for more details."))
+        if is_eventlet:
+            try:
+                from futurist import GreenThreadPoolExecutor
+                tpe_class = GreenThreadPoolExecutor
+            except ImportError:
+                # futurist is not available
+                raise ImportError(
+                    ("Eventlet causes the `concurrent.futures.ThreadPoolExecutor` "
+                     "to hang indefinitely. If you want to use the Eventlet reactor, you "
+                     "need to install the `futurist` package to allow the driver to use "
+                     "the GreenThreadPoolExecutor. See https://github.com/eventlet/eventlet/issues/508 "
+                     "for more details."))
 
         return tpe_class(**kwargs)
 
@@ -5389,11 +5378,9 @@ def __getitem__(self, i):
         self._enter_list_mode("index operator")
         return self._current_rows[i]
 
-    def __nonzero__(self):
+    def __bool__(self):
         return bool(self._current_rows)
 
-    __bool__ = __nonzero__
-
     def get_query_trace(self, max_wait_sec=None):
         """
         Gets the last query trace from the associated future.

cassandra/connection.py

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from __future__ import absolute_import  # to enable import io from stdlib
 from collections import defaultdict, deque
 import errno
 from functools import wraps, partial, total_ordering

cassandra/cqlengine/__init__.py

@@ -26,6 +26,3 @@ class CQLEngineException(Exception):
 class ValidationError(CQLEngineException):
     pass
 
-
-class UnicodeMixin(object):
-    __str__ = lambda x: x.__unicode__()

cassandra/cqlengine/functions.py

@@ -14,12 +14,12 @@
 
 from datetime import datetime
 
-from cassandra.cqlengine import UnicodeMixin, ValidationError
+from cassandra.cqlengine import ValidationError
 
 def get_total_seconds(td):
     return td.total_seconds()
 
-class QueryValue(UnicodeMixin):
+class QueryValue:
     """
     Base class for query filter values. Subclasses of these classes can
     be passed into .filter() keyword args
@@ -31,7 +31,7 @@ def __init__(self, value):
         self.value = value
         self.context_id = None
 
-    def __unicode__(self):
+    def __str__(self):
         return self.format_string.format(self.context_id)
 
     def set_context_id(self, ctx_id):
@@ -109,7 +109,7 @@ def set_columns(self, columns):
     def get_context_size(self):
         return len(self.value)
 
-    def __unicode__(self):
+    def __str__(self):
         token_args = ', '.join('%({0})s'.format(self.context_id + i) for i in range(self.get_context_size()))
         return "token({0})".format(token_args)
 

cassandra/cqlengine/models.py

@@ -272,7 +272,7 @@ class ColumnQueryEvaluator(query.AbstractQueryableColumn):
     def __init__(self, column):
         self.column = column
 
-    def __unicode__(self):
+    def __str__(self):
         return self.column.db_field_name
 
     def _get_column(self):

cassandra/cqlengine/named.py

@@ -52,7 +52,7 @@ class NamedColumn(AbstractQueryableColumn):
     def __init__(self, name):
         self.name = name
 
-    def __unicode__(self):
+    def __str__(self):
         return self.name
 
     def _get_column(self):

cassandra/cqlengine/operators.py

@@ -12,22 +12,21 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from cassandra.cqlengine import UnicodeMixin
 
 
 class QueryOperatorException(Exception):
     pass
 
 
-class BaseQueryOperator(UnicodeMixin):
+class BaseQueryOperator:
     # The symbol that identifies this operator in kwargs
     # ie: colname__<symbol>
     symbol = None
 
     # The comparator symbol this operator uses in cql
     cql_symbol = None
 
-    def __unicode__(self):
+    def __str__(self):
         if self.cql_symbol is None:
             raise QueryOperatorException("cql symbol is None")
         return self.cql_symbol

cassandra/cqlengine/query.py

@@ -19,7 +19,7 @@
 from warnings import warn
 
 from cassandra.query import SimpleStatement, BatchType as CBatchType, BatchStatement
-from cassandra.cqlengine import columns, CQLEngineException, ValidationError, UnicodeMixin
+from cassandra.cqlengine import columns, CQLEngineException, ValidationError
 from cassandra.cqlengine import connection as conn
 from cassandra.cqlengine.functions import Token, BaseQueryFunction, QueryValue
 from cassandra.cqlengine.operators import (InOperator, EqualsOperator, GreaterThanOperator,
@@ -78,7 +78,7 @@ def check_applied(result):
         raise LWTException(result.one())
 
 
-class AbstractQueryableColumn(UnicodeMixin):
+class AbstractQueryableColumn:
     """
     exposes cql query operators through pythons
     builtin comparator symbols
@@ -87,7 +87,7 @@ class AbstractQueryableColumn(UnicodeMixin):
     def _get_column(self):
         raise NotImplementedError
 
-    def __unicode__(self):
+    def __str__(self):
         raise NotImplementedError
 
     def _to_database(self, val):
@@ -405,11 +405,8 @@ def _execute(self, statement):
                 check_applied(result)
             return result
 
-    def __unicode__(self):
-        return str(self._select_query())
-
     def __str__(self):
-        return str(self.__unicode__())
+        return str(self._select_query())
 
     def __call__(self, *args, **kwargs):
         return self.filter(*args, **kwargs)