Corrected BaseCommand.check() signature in docs.

docs/howto/custom-management-commands.txt

@@ -304,7 +304,7 @@ the :meth:`~BaseCommand.handle` method must be implemented.
     It may return a string which will be printed to ``stdout`` (wrapped
     by ``BEGIN;`` and ``COMMIT;`` if :attr:`output_transaction` is ``True``).
 
-.. method:: BaseCommand.check(app_configs=None, tags=None, display_num_errors=False)
+.. method:: BaseCommand.check(app_configs=None, tags=None,display_num_errors=False, include_deployment_checks=False, fail_level=checks.ERROR, databases=None)
 
     Uses the system check framework to inspect the entire Django project for
     potential problems. Serious problems are raised as a :exc:`CommandError`;
@@ -312,8 +312,12 @@ the :meth:`~BaseCommand.handle` method must be implemented.
     ``stdout``.
 
     If ``app_configs`` and ``tags`` are both ``None``, all system checks are
-    performed. ``tags`` can be a list of check tags, like ``compatibility`` or
-    ``models``.
+    performed except deployment and database related checks. ``tags`` can be a
+    list of check tags, like ``compatibility`` or ``models``.
+
+    You can pass ``include_deployment_checks=True`` to also perform deployment
+    checks, and list of database aliases in the ``databases`` to run database
+    related checks against them.
 
 .. _ref-basecommand-subclasses: