Apply yapf formatting to all Python files (issue #2171)

tools/exec_util.py

@@ -5,6 +5,7 @@
 from subprocess import Popen, PIPE
 import sys
 
+
 def exec_cmd(cmd, path, input_string=None):
   """ Execute the specified command and return the result. """
   out = ''
@@ -12,12 +13,21 @@ def exec_cmd(cmd, path, input_string=None):
   parts = cmd.split()
   try:
     if input_string is None:
-      process = Popen(parts, cwd=path, stdout=PIPE, stderr=PIPE,
-                      shell=(sys.platform == 'win32'))
+      process = Popen(
+          parts,
+          cwd=path,
+          stdout=PIPE,
+          stderr=PIPE,
+          shell=(sys.platform == 'win32'))
       out, err = process.communicate()
     else:
-      process = Popen(parts, cwd=path, stdin=PIPE, stdout=PIPE, stderr=PIPE,
-                      shell=(sys.platform == 'win32'))
+      process = Popen(
+          parts,
+          cwd=path,
+          stdin=PIPE,
+          stdout=PIPE,
+          stderr=PIPE,
+          shell=(sys.platform == 'win32'))
       out, err = process.communicate(input=input_string)
   except IOError, (errno, strerror):
     raise