mapping tags => tag names

[Radim]

Hello all,

firstly, thank you for the wonderful pymarc package!

I have a database of records in the Marc XML format (MARC21slim).
Pymarc correctly extracts the records, using `pymarc.map_xml()`, but
I'm wondering how to transform the tags (such as "306") into human
names ("playing time").

Basically I'm looking for a mapping between tags and their names.

Is this built into pymarc? I see records contain a couple of methods
like `title()` and `author()` already.

Or can this mapping be downloaded/extracted from somewhere?

Cheers,
Radim