user: Question: What is the number of monarchs that had Yan Maw La Mon as the heir?
Columns: ['Monarch', 'Heir', 'Status', 'Relationship to Monarch', 'Became heir; reason', 'Ceased to be heir; reason', 'Next in succession']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Wareru', 'Hkun Law', 'Heir presumptive', 'brother', 'December 1287 brother founded dynasty', 'January 1307 succeeded', 'Yan Maw La Mon 1307, brother']
SQL:

assistant: SELECT COUNT("Monarch") FROM "Table" WHERE "Heir" = 'Yan Maw La Mon';