Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_97 ( capacity VARCHAR, rank VARCHAR, city VARCHAR )

### Question ###
What is the capacity of the stadium with a rank lower than 31 located in the city of Bel m ?

### Accurate SQL ###

SELECT capacity FROM table_name_97 WHERE rank < 31 AND city = "belém"