diff --git a/graph.py b/graph.py
index 07a60cd..62c5f89 100755
--- a/graph.py
+++ b/graph.py
@@ -6,14 +6,13 @@
 #
 
 
+import datetime
 import os
+import socket
 import subprocess
 import sys
 import time
 
-from datetime import datetime, timedelta
-from socket import gethostname
-
 from common import *
 
 global gnuplot
@@ -160,8 +159,8 @@ g("set output 'plot.%s'" % OUTPUT_EXT)
 
 g("set multiplot layout 3,1 title \"%s\"" % "\\n\\n\\n")
 
-sdt = datetime.strptime(START_DATE, '%Y-%m-%d-%H:%M:%S')
-edt = datetime.strptime(END_DATE, '%Y-%m-%d-%H:%M:%S')
+sdt = datetime.datetime.strptime(START_DATE, '%Y-%m-%d-%H:%M:%S')
+edt = datetime.datetime.strptime(END_DATE, '%Y-%m-%d-%H:%M:%S')
 delta_t = ((edt - sdt).total_seconds()) / 60.0
 
 g("set title 'cpu load (average = %.2f %%)'" % AVERAGE_LOAD)
@@ -171,12 +170,12 @@ seconds_between = (edt - sdt).total_seconds()
 if seconds_between < 100:
  seconds_between = 100
 
-nsdt = sdt - timedelta(seconds = (seconds_between * 0.01))
-nedt = edt + timedelta(seconds = (seconds_between * 0.01))
+nsdt = sdt - datetime.timedelta(seconds = (seconds_between * 0.01))
+nedt = edt + datetime.timedelta(seconds = (seconds_between * 0.01))
 
 g("set xrange ['%s':'%s']" % (nsdt.strftime("%Y-%m-%d-%H:%M:%S"), nedt.strftime("%Y-%m-%d-%H:%M:%S")));
 
-g("set label 101 at screen 0.02, screen 0.95 'Running on {/:Bold %s} \@ {/:Bold %s}, {/:Bold %d} threads x {/:Bold %s}, total ram: {/:Bold %.2f GB}, total disk space: {/:Bold %.2f GB}' tc rgb 'white'" % (gethostname(), uname, cpus, cpu_name, TOTAL_RAM, TOTAL_FS))
+g("set label 101 at screen 0.02, screen 0.95 'Running on {/:Bold %s} \@ {/:Bold %s}, {/:Bold %d} threads x {/:Bold %s}, total ram: {/:Bold %.2f GB}, total disk space: {/:Bold %.2f GB}' tc rgb 'white'" % (socket.gethostname(), uname, cpus, cpu_name, TOTAL_RAM, TOTAL_FS))
 g("set label 102 at screen 0.02, screen 0.93 'duration: {/:Bold %s} .. {/:Bold %s} (%.2f minutes)' tc rgb 'white'" % (START_DATE, END_DATE, delta_t))
 
 i = 0
diff --git a/watch.py b/watch.py
index 01b3b4d..cc0afbd 100755
--- a/watch.py
+++ b/watch.py
@@ -7,26 +7,24 @@
 
 
 import argparse
+import datetime
+import fcntl
 import os
+import re
+import select
 import signal
 import subprocess
 import sys
 import time
 
-from datetime import datetime
-from select import select
-from fcntl import fcntl, F_GETFL, F_SETFL
-from os.path import realpath
-from re import escape
-
 from common import *
 
-global gnuplot
 global die
 
 die = 0
 
 
+# Declare and parse command line flags
 parser = argparse.ArgumentParser()
 parser.add_argument('session', metavar='SESSION-NAME', type=str, nargs='?', default=None,                help='sargraph session name')
 parser.add_argument('command', metavar='COMMAND',      type=str, nargs='*',                              help='send command')
@@ -104,7 +102,7 @@ if args.session:
 
     if cmd[0] == "start":
         print("Starting sargraph session '%s'" % sid)
-        p = subprocess.Popen(["screen", "-dmSL", sid, realpath(__file__), *sys.argv[3:]])
+        p = subprocess.Popen(["screen", "-dmSL", sid, os.path.realpath(__file__), *sys.argv[3:]])
         while p.poll() is None:
             time.sleep(0.1)
         gpid = 0
@@ -179,10 +177,10 @@ with open("data.txt", "w") as f:
 p.stdout.readline()
 
 if args.fspath:
-    args.fspath = realpath(args.fspath)
+    args.fspath = os.path.realpath(args.fspath)
     with open("/proc/self/mounts", "r") as f:
         while args.fsdev is None:
-            args.fsdev = scan("^(/dev/\S+)\s+%s\s+" % escape(args.fspath), str, f.readline())
+            args.fsdev = scan("^(/dev/\S+)\s+%s\s+" % re.escape(args.fspath), str, f.readline())
     if not args.fsdev:
         print("Error: no device is mounted on %s" % args.fspath)
         sys.exit(1)
@@ -199,14 +197,14 @@ TOTAL_FS = 0
 
 FS_SAR_INDEX = None
 
-flags = fcntl(sys.stdin, F_GETFL)
-fcntl(sys.stdin, F_SETFL, flags | os.O_NONBLOCK)
+flags = fcntl.fcntl(sys.stdin, fcntl.F_GETFL)
+fcntl.fcntl(sys.stdin, fcntl.F_SETFL, flags | os.O_NONBLOCK)
 labels = []
 
 # Gather data from sar output
 while 1:
-    rlist, _, _ = select([p.stdout, sys.stdin], [], [], 0.25)
-    now = datetime.now()
+    rlist, _, _ = select.select([p.stdout, sys.stdin], [], [], 0.25)
+    now = datetime.datetime.now()
     if sys.stdin in rlist:
         label_line = sys.stdin.readline().replace("\n", "")
         if label_line == "q":
@@ -271,8 +269,8 @@ AVERAGE_LOAD = AVERAGE_LOAD / float(i)
 MAX_USED_RAM = MAX_USED_RAM / 1024.0 / 1024.0
 MAX_USED_FS /= 1024.0
 
-sdt = datetime.strptime(START_DATE, '%Y-%m-%d %H:%M:%S')
-edt = datetime.strptime(END_DATE, '%Y-%m-%d %H:%M:%S')
+sdt = datetime.datetime.strptime(START_DATE, '%Y-%m-%d %H:%M:%S')
+edt = datetime.datetime.strptime(END_DATE, '%Y-%m-%d %H:%M:%S')
 delta_t = ((edt - sdt).total_seconds()) / 60.0
 
 with open("data.txt", "a") as f: