'Confirm support for STDDEV and related stats functions
SQLite supports STDDEV as an extension package; so
connection.ops.check_aggregate_support() can\'t unilaterally
rule out support for STDDEV. We need to manually check
whether the call works.'

@cached_property
def supports_stddev(self):

    cursor = self.connection.cursor()
    cursor.execute(u'CREATE    TABLE    STDDEV_TEST    (X    INT)')
    try:
        cursor.execute(u'SELECT    STDDEV(*)    FROM    STDDEV_TEST')
        has_support = True
    except utils.DatabaseError:
        has_support = False
    cursor.execute(u'DROP    TABLE    STDDEV_TEST')
    return has_support
