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some fixes thanks to @adbenitez

Co-Authored-By: Asiel Díaz Benítez <asieldbenitez@gmail.com>

python/CHANGELOG

@@ -5,7 +5,7 @@
 
 - introduced PerAccount and Global hooks that plugins can implement 
 
-- introduced `member_added()` and `member_removed` plugin events. 
+- introduced `member_added()` and `member_removed()` plugin events. 
 
 - introduced two documented examples for an echo and a group-membership
   tracking plugin. 

python/src/deltachat/__init__.py

@@ -103,7 +103,7 @@ def run_cmdline(argv=None, account_plugins=None):
     if argv is None:
         argv = sys.argv
 
-    parser = argparse.ArgumentParser(prog="simple-echo")
+    parser = argparse.ArgumentParser(prog=argv[0] if argv else None)
     parser.add_argument("--show-ffi", action="store_true", help="show low level ffi events")
     parser.add_argument("--db", action="store", help="database file")
     parser.add_argument("--email", action="store", help="email address")