python – picloud上发布的函数抛出错误

{“error”: {“msg”: “Function arguments (POST data) are not valid JSON“,“code”: 446,“data”: “{‘parameter’: u’ filename’}”,“retry”: false}}

我已将函数的输出编码设置为raw,我也按照文档详细说明了.

以下是一些功能细节.

功能名称：探测器(名称,ifile)
有两个参数,一个图像文件及其名称

以下是代码的相关部分：

#all needed classes and libraries have been imported,urlfetch,poster,MultipartParam class ect.

#here we go! 
params=[] 
params.append(MultipartParam("Imagename",filename="anyname.jpg",filetype="application/octet-stream",value=some_file_uploaded_via_html_form))
 #http_headers has been defined with appropriate autorization credentials 
datagen,headers=multipart.encode(params) 
data=str().join(datagen)

result=urlfetch.fetch(url=my_defined_function_url,payload=data,method=urlfetch.POST,headers=http_headers)
 print result.content

当我添加以下行时,为了包含实际的函数参数

params.append(MultipartParam('name',value=filename_variable) 
params.append(MultipartParam('ifile',value=some_file_uploaded_via_html_form)

我收到了错误

{“error”: {“msg”: ” charset is defined multiple times”,“code”: 445,“retry”: false}}

我也尝试将参数包装在字典中,而不是单独的MultipartParam实例

请帮忙.