Parse command line arguments.

        This method relies on ``context.argv`` and ``context.early_parser``
        and produces ``context.args``. Note that ``.argv`` is modified by
        :meth:`preparse()` so it actually has _less_ things in it.

        The ``context.args`` object is the return value from argparse.
        It is the dict/object like namespace object.

def parse(self, context):
        """
        Parse command line arguments.

        This method relies on ``context.argv`` and ``context.early_parser``
        and produces ``context.args``. Note that ``.argv`` is modified by
        :meth:`preparse()` so it actually has _less_ things in it.

        The ``context.args`` object is the return value from argparse.
        It is the dict/object like namespace object.
        """
        context.args = context.parser.parse_args(context.argv)