fix #4533

lib/util.py

@@ -330,7 +330,10 @@ def android_data_dir():
 def android_headers_dir():
     d = android_ext_dir() + '/org.electrum.electrum'
     if not os.path.exists(d):
+        try:
             os.mkdir(d)
+        except FileExistsError:
+            pass  # in case of race
     return d
 
 def android_check_data_dir():