从ROBOT框架中的python模块调用特定方法

有一个具有2个类的Python模块。每个类都有一组定义的函数或方法。我们如何从ROBOT框架的类中调用特定方法。我正在尝试下面的方法，但是它给出了以下错误。有人可以帮我解决这里的问题。Python模块和Robot文件在同一路径中。我尝试将库语句更改为CheckCode.employee WITH_NAME xyz。这没有帮助。谢谢。

ERRORS
==============

[ WARN ] Imported library '/homes/user/New/CheckCode.py' contains no keywords.
==============================================================================
CheckCode :: Checking small built in code                                     
==============================================================================
Verify we can call a particular class from a Python Module in Robot   | FAIL |
No keyword with name 'my_code.employee.staff info' found.
------------------------------------------------------------------------------
CheckCode :: Checking small built in code                             | FAIL |
1 critical test, 0 passed, 1 failed
1 test total, 0 passed, 1 failed
==============================================================================


Python Module File output
******************************

import re
import collections
import math

class person():
    def __init__(self,first,last):
        self.firstname = first
        self.lastname = last

    def emp_name(self):
        return self.firstname + " " + self.lastname

class employee(person):
    def __init__(self,first,last,empId):
        person.__init__(self,first,last)
        self.staffId = empId

    def staff_info(self):
        return self.Name() + " " + self.staffId

ROBOT FILE 
******************************

*** Settings ***
Documentation    Checking small built in code
Library   BuiltIn
Library   Collections
Library   CheckCode.py     WITH NAME   my_code

*** Test Cases ***
Verify we can call a particular class from a Python Module in Robot
    Log     Hello World
    ${var} =    my_code.employee.staff info     Maggi       Nestle      20000


*** Keywords ***
Init
    Set Log Level    DEBUG