diff --git a/git_command.py b/git_command.py
index 51e856a..6e28522 100644
--- a/git_command.py
+++ b/git_command.py
@@ -249,7 +249,7 @@ class GitCommand(object):
                project,
                cmdv,
                bare=False,
-               provide_stdin=False,
+               input=None,
                capture_stdout=False,
                capture_stderr=False,
                merge_output=False,
@@ -298,11 +298,7 @@ class GitCommand(object):
         command.append('--progress')
     command.extend(cmdv[1:])
 
-    if provide_stdin:
-      stdin = subprocess.PIPE
-    else:
-      stdin = None
-
+    stdin = subprocess.PIPE if input else None
     stdout = subprocess.PIPE
     stderr = subprocess.STDOUT if merge_output else subprocess.PIPE
 
@@ -350,7 +346,11 @@ class GitCommand(object):
       _add_ssh_client(p)
 
     self.process = p
-    self.stdin = p.stdin
+    if input:
+      if isinstance(input, str):
+        input = input.encode('utf-8')
+      p.stdin.write(input)
+      p.stdin.close()
 
   @staticmethod
   def _GetBasicEnv():
diff --git a/subcmds/cherry_pick.py b/subcmds/cherry_pick.py
index c333fcf..4b7f141 100644
--- a/subcmds/cherry_pick.py
+++ b/subcmds/cherry_pick.py
@@ -72,11 +72,9 @@ change id will be added.
       new_msg = self._Reformat(old_msg, sha1)
 
       p = GitCommand(None, ['commit', '--amend', '-F', '-'],
-                     provide_stdin=True,
+                     input=new_msg,
                      capture_stdout=True,
                      capture_stderr=True)
-      p.stdin.write(new_msg)
-      p.stdin.close()
       if p.Wait() != 0:
         print("error: Failed to update commit message", file=sys.stderr)
         sys.exit(1)