connect here - use the other classes cls_oracle, cls_mysql, etc
        otherwise this has the credentials used to access a share folder

def login(self, schema, username, password):
        """
        connect here - use the other classes cls_oracle, cls_mysql, etc
        otherwise this has the credentials used to access a share folder
        """
        self.schema = schema
        self.username = username
        self.password = password
        self.connection = schema