diff --git a/Tools/BuildSlaveSupport/ews-build/buildbot.tac b/Tools/BuildSlaveSupport/ews-build/buildbot.tac
index fda62c5..0ff3d64 100644
--- a/Tools/BuildSlaveSupport/ews-build/buildbot.tac
+++ b/Tools/BuildSlaveSupport/ews-build/buildbot.tac
@@ -10,7 +10,7 @@
 configfile = 'master.cfg'
 
 # Default umask for server
-umask = 022
+umask = 0o022
 
 # if this is a relocatable tac file, get the directory containing the TAC
 if basedir == '.':
diff --git a/Tools/BuildSlaveSupport/ews-build/steps.py b/Tools/BuildSlaveSupport/ews-build/steps.py
index 948a714..c59aaed 100644
--- a/Tools/BuildSlaveSupport/ews-build/steps.py
+++ b/Tools/BuildSlaveSupport/ews-build/steps.py
@@ -1230,7 +1230,7 @@
     def __init__(self, **kwargs):
         kwargs['workersrc'] = self.workersrc
         kwargs['masterdest'] = self.masterdest
-        kwargs['mode'] = 0644
+        kwargs['mode'] = 0o0644
         kwargs['blocksize'] = 1024 * 256
         transfer.FileUpload.__init__(self, **kwargs)
 
@@ -1507,7 +1507,7 @@
             identifier = '-{}'.format(identifier)
         kwargs['workersrc'] = self.workersrc
         kwargs['masterdest'] = Interpolate('public_html/results/%(prop:buildername)s/r%(prop:patch_id)s-%(prop:buildnumber)s{}.zip'.format(identifier))
-        kwargs['mode'] = 0644
+        kwargs['mode'] = 0o0644
         kwargs['blocksize'] = 1024 * 256
         transfer.FileUpload.__init__(self, **kwargs)
 
diff --git a/Tools/ChangeLog b/Tools/ChangeLog
index 3288c63..9b92384 100644
--- a/Tools/ChangeLog
+++ b/Tools/ChangeLog
@@ -1,3 +1,13 @@
+2019-10-15  Aakash Jain  <aakash_jain@apple.com>
+
+        [ews] Use python 3 compatible way to represent octal in buildbot code
+        https://bugs.webkit.org/show_bug.cgi?id=202999
+
+        Reviewed by Jonathan Bedard.
+
+        * BuildSlaveSupport/ews-build/buildbot.tac:
+        * BuildSlaveSupport/ews-build/steps.py:
+
 2019-10-15  Jonathan Bedard  <jbedard@apple.com>
 
         results.webkit.org: Add os version to various unix ports