<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _get_sql(filename):
 """Returns the contents of the sql file from the given ``filename``."""

    with open(os.path.join(SQL_DIR, filename), 'r') as f:
        return f.read()