PEP8 optimize imports (#242)

To make them PEP8-compliant

17 files changed, 55 insertions, 40 deletions

diff --git a/pysnmp/carrier/asyncio/dgram/base.py b/pysnmp/carrier/asyncio/dgram/base.py
index 7cc0b589..ae5ab3a7 100644
--- a/pysnmp/carrier/asyncio/dgram/base.py
+++ b/pysnmp/carrier/asyncio/dgram/base.py
@@ -30,18 +30,20 @@
 # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 # THE POSSIBILITY OF SUCH DAMAGE.
 #
-import sys
 import platform
+import sys
 import traceback
-from pysnmp.carrier.asyncio.base import AbstractAsyncioTransport
-from pysnmp.carrier import error
-from pysnmp import debug
 
 try:
     import asyncio
+
 except ImportError:
     import trollius as asyncio
 
+from pysnmp import debug
+from pysnmp.carrier import error
+from pysnmp.carrier.asyncio.base import AbstractAsyncioTransport
+
 IS_PYTHON_344_PLUS = platform.python_version_tuple() >= ('3', '4', '4')
 
 
diff --git a/pysnmp/carrier/asyncio/dgram/udp.py b/pysnmp/carrier/asyncio/dgram/udp.py
index b13d4202..1c056d5a 100644
--- a/pysnmp/carrier/asyncio/dgram/udp.py
+++ b/pysnmp/carrier/asyncio/dgram/udp.py
@@ -31,8 +31,9 @@
 # THE POSSIBILITY OF SUCH DAMAGE.
 #
 import socket
-from pysnmp.carrier.base import AbstractTransportAddress
+
 from pysnmp.carrier.asyncio.dgram.base import DgramAsyncioProtocol
+from pysnmp.carrier.base import AbstractTransportAddress
 
 domainName = snmpUDPDomain = (1, 3, 6, 1, 6, 1, 1)
 
diff --git a/pysnmp/carrier/asyncio/dgram/udp6.py b/pysnmp/carrier/asyncio/dgram/udp6.py
index d9bd6bfe..43c2232c 100644
--- a/pysnmp/carrier/asyncio/dgram/udp6.py
+++ b/pysnmp/carrier/asyncio/dgram/udp6.py
@@ -5,9 +5,9 @@
 # License: http://snmplabs.com/pysnmp/license.html
 #
 import socket
-from pysnmp.carrier.base import AbstractTransportAddress
-from pysnmp.carrier.asyncio.dgram.base import DgramAsyncioProtocol
 
+from pysnmp.carrier.asyncio.dgram.base import DgramAsyncioProtocol
+from pysnmp.carrier.base import AbstractTransportAddress
 
 domainName = snmpUDP6Domain = (1, 3, 6, 1, 2, 1, 100, 1, 2)
 
diff --git a/pysnmp/carrier/asyncio/dispatch.py b/pysnmp/carrier/asyncio/dispatch.py
index da1399b4..cb9f2020 100644
--- a/pysnmp/carrier/asyncio/dispatch.py
+++ b/pysnmp/carrier/asyncio/dispatch.py
@@ -30,9 +30,10 @@
 # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 # THE POSSIBILITY OF SUCH DAMAGE.
 #
-import sys
 import platform
+import sys
 import traceback
+
 from pysnmp.carrier.base import AbstractTransportDispatcher
 from pysnmp.error import PySnmpError
 
diff --git a/pysnmp/carrier/asyncore/base.py b/pysnmp/carrier/asyncore/base.py
index 035dcbab..f7b1af9e 100644
--- a/pysnmp/carrier/asyncore/base.py
+++ b/pysnmp/carrier/asyncore/base.py
@@ -4,13 +4,14 @@
 # Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
 # License: http://snmplabs.com/pysnmp/license.html
 #
+import asyncore
 import socket
 import sys
-import asyncore
+
+from pysnmp import debug
 from pysnmp.carrier import error
-from pysnmp.carrier.base import AbstractTransport
 from pysnmp.carrier.asyncore.dispatch import AsyncoreDispatcher
-from pysnmp import debug
+from pysnmp.carrier.base import AbstractTransport
 
 
 class AbstractSocketTransport(asyncore.dispatcher, AbstractTransport):
diff --git a/pysnmp/carrier/asyncore/dgram/base.py b/pysnmp/carrier/asyncore/dgram/base.py
index f103e781..e456da20 100644
--- a/pysnmp/carrier/asyncore/dgram/base.py
+++ b/pysnmp/carrier/asyncore/dgram/base.py
@@ -4,20 +4,22 @@
 # Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
 # License: http://snmplabs.com/pysnmp/license.html
 #
-import socket
 import errno
-import sys
-from pysnmp.carrier.asyncore.base import AbstractSocketTransport
-from pysnmp.carrier import sockfix, sockmsg, error
+import socket
+
 from pysnmp import debug
+from pysnmp.carrier import sockmsg, error
+from pysnmp.carrier.asyncore.base import AbstractSocketTransport
 
 # Ignore these socket errors
-SOCK_ERRORS = {errno.ESHUTDOWN: True,
-               errno.ENOTCONN: True,
-               errno.ECONNRESET: False,
-               errno.ECONNREFUSED: False,
-               errno.EAGAIN: False,
-               errno.EWOULDBLOCK: False}
+SOCK_ERRORS = {
+    errno.ESHUTDOWN: True,
+    errno.ENOTCONN: True,
+    errno.ECONNRESET: False,
+    errno.ECONNREFUSED: False,
+    errno.EAGAIN: False,
+    errno.EWOULDBLOCK: False
+}
 
 if hasattr(errno, 'EBADFD'):
     # bad FD may happen upon FD closure on n-1 select() event
diff --git a/pysnmp/carrier/asyncore/dgram/udp.py b/pysnmp/carrier/asyncore/dgram/udp.py
index 60bc32a9..079555ae 100644
--- a/pysnmp/carrier/asyncore/dgram/udp.py
+++ b/pysnmp/carrier/asyncore/dgram/udp.py
@@ -5,8 +5,9 @@
 # License: http://snmplabs.com/pysnmp/license.html
 #
 from socket import AF_INET
-from pysnmp.carrier.base import AbstractTransportAddress
+
 from pysnmp.carrier.asyncore.dgram.base import DgramSocketTransport
+from pysnmp.carrier.base import AbstractTransportAddress
 
 DOMAIN_NAME = SNMP_UDP_DOMAIN = (1, 3, 6, 1, 6, 1, 1)
 
diff --git a/pysnmp/carrier/asyncore/dgram/udp6.py b/pysnmp/carrier/asyncore/dgram/udp6.py
index 26af0ba5..75d348d6 100644
--- a/pysnmp/carrier/asyncore/dgram/udp6.py
+++ b/pysnmp/carrier/asyncore/dgram/udp6.py
@@ -4,11 +4,11 @@
 # Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
 # License: http://snmplabs.com/pysnmp/license.html
 #
-from pysnmp.carrier import sockfix
-from pysnmp.carrier.base import AbstractTransportAddress
-from pysnmp.carrier.asyncore.dgram.base import DgramSocketTransport
 import socket
 
+from pysnmp.carrier.asyncore.dgram.base import DgramSocketTransport
+from pysnmp.carrier.base import AbstractTransportAddress
+
 DOMAIN_NAME = SNMP_UDP6_DOMAIN = (1, 3, 6, 1, 2, 1, 100, 1, 2)
 
 
diff --git a/pysnmp/carrier/asyncore/dgram/unix.py b/pysnmp/carrier/asyncore/dgram/unix.py
index 486c84f8..0f68f962 100644
--- a/pysnmp/carrier/asyncore/dgram/unix.py
+++ b/pysnmp/carrier/asyncore/dgram/unix.py
@@ -11,6 +11,7 @@ try:
     from socket import AF_UNIX
 except ImportError:
     AF_UNIX = None
+
 from pysnmp.carrier.base import AbstractTransportAddress
 from pysnmp.carrier.asyncore.dgram.base import DgramSocketTransport
 
diff --git a/pysnmp/carrier/asyncore/dispatch.py b/pysnmp/carrier/asyncore/dispatch.py
index 3517bdff..897fdd0c 100644
--- a/pysnmp/carrier/asyncore/dispatch.py
+++ b/pysnmp/carrier/asyncore/dispatch.py
@@ -4,11 +4,12 @@
 # Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
 # License: http://snmplabs.com/pysnmp/license.html
 #
-from time import time
+from asyncore import loop
+from asyncore import socket_map
 from sys import exc_info
+from time import time
 from traceback import format_exception
-from asyncore import socket_map
-from asyncore import loop
+
 from pysnmp.carrier.base import AbstractTransportDispatcher
 from pysnmp.error import PySnmpError
 
diff --git a/pysnmp/carrier/asynsock/dispatch.py b/pysnmp/carrier/asynsock/dispatch.py
index 478d9e49..74d14141 100644
--- a/pysnmp/carrier/asynsock/dispatch.py
+++ b/pysnmp/carrier/asynsock/dispatch.py
@@ -6,4 +6,5 @@
 #
 from pysnmp.carrier.asyncore.dispatch import *
 
+
 AsynsockDispatcher = AsyncoreDispatcher
diff --git a/pysnmp/carrier/sockfix.py b/pysnmp/carrier/sockfix.py
index edfc1631..bba068fa 100644
--- a/pysnmp/carrier/sockfix.py
+++ b/pysnmp/carrier/sockfix.py
@@ -8,7 +8,6 @@ import socket
 
 from pysnmp import debug
 
-
 SYMBOLS = {
     'IP_PKTINFO': 8,
     'IP_TRANSPARENT': 19,
diff --git a/pysnmp/carrier/twisted/base.py b/pysnmp/carrier/twisted/base.py
index 91883d7d..21c16a42 100644
--- a/pysnmp/carrier/twisted/base.py
+++ b/pysnmp/carrier/twisted/base.py
@@ -12,8 +12,8 @@
 #
 # Description: twisted DatagramProtocol UDP transport
 #
-from pysnmp.carrier.twisted.dispatch import TwistedDispatcher
 from pysnmp.carrier.base import AbstractTransport
+from pysnmp.carrier.twisted.dispatch import TwistedDispatcher
 
 
 class AbstractTwistedTransport(AbstractTransport):
diff --git a/pysnmp/carrier/twisted/dgram/base.py b/pysnmp/carrier/twisted/dgram/base.py
index 42eb7c04..c752e580 100644
--- a/pysnmp/carrier/twisted/dgram/base.py
+++ b/pysnmp/carrier/twisted/dgram/base.py
@@ -4,12 +4,12 @@
 # Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
 # License: http://snmplabs.com/pysnmp/license.html
 #
-import sys
-from twisted.internet.protocol import DatagramProtocol
 from twisted.internet import reactor
-from pysnmp.carrier.twisted.base import AbstractTwistedTransport
-from pysnmp.carrier import error
+from twisted.internet.protocol import DatagramProtocol
+
 from pysnmp import debug
+from pysnmp.carrier import error
+from pysnmp.carrier.twisted.base import AbstractTwistedTransport
 
 
 class DgramTwistedTransport(DatagramProtocol, AbstractTwistedTransport):
diff --git a/pysnmp/carrier/twisted/dgram/udp.py b/pysnmp/carrier/twisted/dgram/udp.py
index eb47bb24..10cf946f 100644
--- a/pysnmp/carrier/twisted/dgram/udp.py
+++ b/pysnmp/carrier/twisted/dgram/udp.py
@@ -4,11 +4,11 @@
 # Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
 # License: http://snmplabs.com/pysnmp/license.html
 #
-import sys
 from twisted.internet import reactor
+
+from pysnmp.carrier import error
 from pysnmp.carrier.base import AbstractTransportAddress
 from pysnmp.carrier.twisted.dgram.base import DgramTwistedTransport
-from pysnmp.carrier import error
 
 DOMAIN_NAME = SNMP_UDP_DOMAIN = (1, 3, 6, 1, 6, 1, 1)
 
diff --git a/pysnmp/carrier/twisted/dgram/unix.py b/pysnmp/carrier/twisted/dgram/unix.py
index 24fdc5c7..6ce3cde2 100644
--- a/pysnmp/carrier/twisted/dgram/unix.py
+++ b/pysnmp/carrier/twisted/dgram/unix.py
@@ -4,11 +4,11 @@
 # Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
 # License: http://snmplabs.com/pysnmp/license.html
 #
-import sys
 from twisted.internet import reactor
+
+from pysnmp.carrier import error
 from pysnmp.carrier.base import AbstractTransportAddress
 from pysnmp.carrier.twisted.dgram.base import DgramTwistedTransport
-from pysnmp.carrier import error
 
 DOMAIN_NAME = SNMP_LOCAL_DOMAIN = (1, 3, 6, 1, 2, 1, 100, 1, 13)
 
diff --git a/pysnmp/carrier/twisted/dispatch.py b/pysnmp/carrier/twisted/dispatch.py
index cacc20b4..77f5c168 100644
--- a/pysnmp/carrier/twisted/dispatch.py
+++ b/pysnmp/carrier/twisted/dispatch.py
@@ -12,8 +12,13 @@
 #
 # Description: Transport dispatcher based on twisted.internet.reactor
 #
-import sys, time, traceback
-from twisted.internet import reactor, task
+import sys
+import time
+import traceback
+
+from twisted.internet import reactor
+from twisted.internet import task
+
 from pysnmp.carrier.base import AbstractTransportDispatcher
 from pysnmp.error import PySnmpError