def set_pkg_cr_text(self, doc, text):
self.assert_package_exists()<EOL>if not self.package_cr_text_set:<EOL><INDENT>self.package_cr_text_set = True<EOL>doc.package.cr_text = text<EOL><DEDENT>else:<EOL><INDENT>raise CardinalityError('<STR_LIT>')<EOL><DEDENT>
Sets the package's license comment.
        Raises OrderError if no package previously defined.
        Raises CardinalityError if already set.