Returns the singleton connection to the SQLite3 database.

        :param dbname: The database name
        :type dbname: str

def get(cls, dbname="perfdump"):
        """Returns the singleton connection to the SQLite3 database.

        :param dbname: The database name
        :type dbname: str
        
        """
        try:
            return cls.connection
        except:
            cls.connect(dbname)
            return cls.connection