@remove_hairs_decorator<EOL><INDENT>def get_publisher(self, undefined="<STR_LIT>"):<DEDENT>
publishers = set([<EOL>remove_hairs_fn(publisher)<EOL>for publisher in self["<STR_LIT>"] + self["<STR_LIT>"]<EOL>])<EOL>return _undefined_pattern(<EOL>"<STR_LIT:U+002CU+0020>".join(publishers),<EOL>lambda x: x.strip() == "<STR_LIT>",<EOL>undefined<EOL>)<EOL>
Args:
    undefined (optional): Argument, which will be returned if the
              `publisher` record is not found.

Returns:
    str: Name of the publisher ("``Grada``" for example) or \
         `undefined` if `publisher` is not found.