python引用另一个py文件中的类中函数

1.获取gpu信息的文件gpu_info.py

cat gpu_info.py 
import pynvml   #获取GPU信息

 
class GpuInfo(object):
    def __init__(self):
        #初始化
        pynvml.nvmlInit()
 
    def get_gpu_device(self):
        deviceCount = pynvml.nvmlDeviceGetCount()
        gpu_list = []
        for i in range(deviceCount):
            handle = pynvml.nvmlDeviceGetHandleByIndex(i)
            print("GPU", i, ":", pynvml.nvmlDeviceGetName(handle))
            gpu_list.append(i)
        return gpu_list
 
    def get_free_rate(self, gpu_id):
        handle = pynvml.nvmlDeviceGetHandleByIndex(gpu_id)
        info = pynvml.nvmlDeviceGetMemoryInfo(handle)
        free_rate = int((info.free / info.total) * 100)
        return free_rate
 
    def get_gpu_info(self, gpu_id):
        handle = pynvml.nvmlDeviceGetHandleByIndex(gpu_id)
        info = pynvml.nvmlDeviceGetMemoryInfo(handle)
        M = 1024*1024
        gpu_info = "id:{}  total:{}M free:{}M  used:{}M free_rate:{}%".format(gpu_id, info.total/M, info.free/M, info.used/M, self.get_free_rate(gpu_id))
    
        return gpu_info
 
    def release(self):
        #最后要关闭管理工具
        pynvml.nvmlShutdown()
    
 
if __name__ == "__main__":

    print("GPU INFO----------------------------")
    gpu_info = GpuInfo()
    gpu_devices = gpu_info.get_gpu_device()
    print("GPU USE INFO----------------------------")
    for gpuid in gpu_devices:
        print(gpu_info.get_gpu_info(gpuid))
    gpu_info.release()


2. 引用gpu_info.py文件
cat app.py 

from gpu_info import GpuInfo

gf = GpuInfo()
a = gf.get_gpu_device()
print(a)