diff --git a/platformio/builder/tools/platformio.py b/platformio/builder/tools/platformio.py
index 0415c79f..c3acf555 100644
--- a/platformio/builder/tools/platformio.py
+++ b/platformio/builder/tools/platformio.py
@@ -75,7 +75,8 @@ def BuildProgram(env):
         env.Append(_LIBFLAGS=" -Wl,--end-group")
 
     program = env.Program(
-        os.path.join("$BUILD_DIR", env.subst("$PROGNAME$PROGSUFFIX")), env["PIOBUILDFILES"]
+        os.path.join("$BUILD_DIR", env.subst("$PROGNAME$PROGSUFFIX")),
+        env["PIOBUILDFILES"],
     )
     env.Replace(PIOMAINPROG=program)