docstr: Set up any connections required by the handler
  Should return output of check_connection() method after attempting
  connection. Should switch self.is_connected.
  Returns:
      Connection Object
docstr_tok: ["Set","up","any","connections","required","by","the","handler","Should","return","output","of","check_connection","(",")","method","after","attempting","connection",".","Should","switch","self.is_connected",".","Returns",":","Connection","Object"]
code: def connect(self):
      """Set up any connections required by the handler
      Should return output of check_connection() method after attempting
      connection. Should switch self.is_connected.
      Returns:
          Connection Object
      """
      if self.is_connected is True:
          return self.connection
  
      user = self.connection_config.get("user")
      password = self.connection_config.get("password")
      jdbc_class = self.connection_config.get("jdbcClass")
      jar_location = self.connection_config.get("jdbcJarLocation")
  
      jdbc_url = (
          "jdbc:derby://"
          + self.host
          + ":"
          + self.port
          + "/"
          + self.database
          + ";"
      )
  
      if not jdbc_class:
          jdbc_class = "org.apache.derby.jdbc.ClientDriver"
  
      if user:
          self.schema = user
  
      try:
          if user and password and jar_location:
              self.connection = jdbcconnector.connect(
                  jclassname=jdbc_class,
                  url=jdbc_url,
                  driver_args=[user, password],
                  jars=jar_location.split(","),
              )
          elif user and password:
              self.connection = jdbcconnector.connect(
                  jclassname=jdbc_class,
                  url=jdbc_url,
                  driver_args=[user, password],
              )
          elif jar_location:
              self.connection = jdbcconnector.connect(
                  jclassname=jdbc_class,
                  url=jdbc_url,
                  jars=jar_location.split(","),
              )
          else:
              self.connection = jdbcconnector.connect(
                  jdbc_class, jdbc_url
              )
      except Exception as e:
          logger.error(
              f"Error while connecting to {self.database}, {e}"
          )
  
      return self.connection
  
imports: from collections import OrderedDict
  from typing import Optional
  from mindsdb_sql.parser.ast.base import ASTNode
  from mindsdb.integrations.libs.base import DatabaseHandler
  from mindsdb.utilities import log
  from mindsdb_sql import parse_sql
  from mindsdb.integrations.libs.response import HandlerStatusResponse, HandlerResponse, RESPONSE_TYPE
  from mindsdb.integrations.libs.const import HANDLER_CONNECTION_ARG_TYPE
  import pandas
  import jaydebeapi
label_desc: Use image node_id 2 for calling the DerbyHandler obj's underlying member method code with example usage: obj.connect() and returns: self, self