Verify that given units for a particular tag are correct.
Look for and parse the magres file format version line
Parse atoms block into data dictionary given list of record tuples.
Parse block contents into a series of (tag, data) records
Parse series of XML-like deliminated blocks into a list of (block_name, contents) tuples
Parse any other block into data dictionary given list of record tuples.
Parse magres block into data dictionary given list of record tuples.
Write out a <magres> block from its dictionary representation