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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def run_script(script_path, session, handle_command=None, handle_line=None):
 """ Run a script file using a valid sqlalchemy session. Based on https://bit.ly/2CToAhY. See also sqlalchemy transaction control: https://bit.ly/2yKso0A :param script_path: The path where the script is located :param session: A sqlalchemy session to execute the sql commands from the script :param handle_command: Function to handle a valid command :param handle_line: Function to handle a valid line :return: """

    logger.debug("Opening script %s." % script_path)
    with open(script_path, "r") as stream:
        sql_command = ""
        for line in stream:
            # Ignore commented lines
            if not line.startswith("--") and line.strip("\n"):
                # Append line to the command string
                if handle_line is not None:
                    logger.debug("Calling the handle line function for: "
                                 "%s." % line)
                    line = handle_line(line)
                sql_command = "%s%s" % (sql_command, line.strip("\n"))
                # If the command string ends with ";", it is a full statement
                if sql_command.endswith(";"):
                    # Try to execute statement and commit it
                    try:
                        if handle_command is not None:
                            logger.debug("Calling the handle command function "
                                         "for: %s." % sql_command)
                            sql_command = handle_command(sql_command)
                        session.execute(text(sql_command))
                    # Assert in case of error
                    except Exception as e:
                        session.rollback()
                        raise e
                    # Finally, clear command string
                    finally:
                        sql_command = ""
    session.commit()