diff --git a/shtab/__init__.py b/shtab/__init__.py
index e29a2e9..683172f 100644
--- a/shtab/__init__.py
+++ b/shtab/__init__.py
@@ -245,9 +245,6 @@ def recurse(parser, prefix):
         options_strings_str = "' '".join(get_option_strings(parser))
         option_strings.append(f"{prefix}_option_strings=('{options_strings_str}')")
         for optional in parser._get_optional_actions():
-            if optional == SUPPRESS:
-                continue
-
             for option_string in optional.option_strings:
                 if hasattr(optional, "complete"):
                     # shtab `.complete = ...` functions
@@ -440,8 +437,7 @@ def complete_bash(parser, root_prefix=None, preamble="", choice_functions=None):
   if [[ $pos_only = 0 && "${completing_word}" == -* ]]; then
     # optional argument started: use option strings
     COMPREPLY=( $(compgen -W "${current_option_strings[*]}" -- "${completing_word}") )
-  elif [[ "${previous_word}" == ">" || "${previous_word}" == ">>" ||
-          "${previous_word}" =~ ^[12]">" || "${previous_word}" =~ ^[12]">>" ]]; then
+  elif [[ "${previous_word}" =~ ^[0-9\\&]*[\\<\\>]\\>?$ ]]; then
     # handle redirection operators
     COMPREPLY=( $(compgen -f -- "${completing_word}") )
   else
diff --git a/shtab/__main__.py b/shtab/__main__.py
index 22c6f14..1018735 100644
--- a/shtab/__main__.py
+++ b/shtab/__main__.py
@@ -1,8 +1,7 @@
 import logging
-import sys
 
 from .main import main
 
 if __name__ == "__main__":
     logging.basicConfig(level=logging.INFO)
-    sys.exit(main(sys.argv[1:]) or 0)
+    main()
diff --git a/tests/test_shtab.py b/tests/test_shtab.py
index d730151..8e9161d 100644
--- a/tests/test_shtab.py
+++ b/tests/test_shtab.py
@@ -315,7 +315,7 @@ def test_add_argument_to_positional(shell, caplog, capsys):
         completion_manual = shtab.complete(parser, shell=shell)
         with pytest.raises(SystemExit) as exc:
             sub._actions[-1](sub, Namespace(), shell)
-            assert exc.type == SystemExit
+            assert exc.type is SystemExit
             assert exc.value.code == 0
     completion, err = capsys.readouterr()
     print(completion)