json.dump()、json.dumps(),序列化(encoder)将字典转成json格式字符串，以便传输存储。
json.load()、json.loads(),反序列化(decoder)json格式字符串转换成字典，便于分析处理。

# if  one filefield  upload muti files use ：
files=  [
    (
    "field1",open("test1.png","rb")
    ),
    (
    ‘filed2‘,open(‘a2.xlsx‘,‘rb‘).read()
    )
 ]

# if multi field upload several files use:

files= {
"field1" : ("filepath中的文件名称", open("filePath1", "rb")),
  "field2" : ("filename2", open("filePath2", "rb"), "image/jpeg"),
  "field3" : ("filename3", open("filePath3", "rb"), "image/jpeg", {"refer" : "localhost"})
}

upload request files