Azure Devops Upload Image

Question

I am importing a lot of data into Azure Devops using python. I have all the pieces working. I can upload images, my issue is when I download the image from the Devops website it is not a valid file. I will share my image upload code.

def convertAttachmentToJsonBinary(attachmentPath):
    file = open(attachmentPath, 'rb')
    file_data = file.read()
    encoded_data = base64.b64encode(file_data)
    decoded_data = encoded_data.decode()
    data = "[" + decoded_data + "]"
    return data


def patchWorkItemWithAttachment(case_id, att_id, att_url):
    json_template = open("attachment.json", "r")
    json_data = json.load(json_template)
    json_data[0]['value']['url'] = att_url
    json_data[0]['value']['attributes']['comment'] = "Adding attachment"

    response = requests.patch(patch_workitem_url.replace("{id}", case_id), json=json_data, headers=headers)
    print(response.json())

While I am uploading a new case, I create the case, add attachments, then patch the newly created case with the new attachment. Again all of this work. I can see the attachment in my case online, however when I download it the file is invalid.