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_101336_1 (crystal_structure VARCHAR, formula VARCHAR)

### Question ###
What is the crystal structure for the formula yba 2 cu 3 o 7?

### Accurate SQL ###

SELECT crystal_structure FROM table_101336_1 WHERE formula = "YBa 2 Cu 3 O 7"