a bytes-like object is required, not 'str'

TypeError at /admin/goods/goodssku/add/

a bytes-like object is required, not 'str'

Request Method:	POST
Request URL:	http://127.0.0.1:8000/admin/goods/goodssku/add/
Django Version:	1.8.2
Exception Type:	TypeError
Exception Value:	a bytes-like object is required, not 'str'
Exception Location:	/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/django/core/files/storage.py in save, line 67
Python Executable:	/Library/Frameworks/Python.framework/Versions/3.5/bin/python3
Python Version:	3.5.1
Python Path:	['/Users/mac/PycharmProjects/dailyfresh/apps', '/Users/mac/PycharmProjects/dailyfresh', '/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pip-10.0.1-py3.5.egg', '/Users/mac/PycharmProjects/dailyfresh', '/Applications/PyCharm.app/Contents/helpers/pycharm_display', '/Library/Frameworks/Python.framework/Versions/3.5/lib/python35.zip', '/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5', '/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/plat-darwin', '/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/lib-dynload', '/Users/mac/Library/Python/3.5/lib/python/site-packages', '/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages', '/Applications/PyCharm.app/Contents/helpers/pycharm_matplotlib_backend', '/Users/mac/PycharmProjects/dailyfresh']
Server time:	星期四, 7 一月 2021 16:54:20 +0800

原因是_save（）方法返回的是str类型而并非是byte类型

修改之前：

def _save(self,name,content):
    '''保存文件时使用'''
    # name:你选择上传文件的名字 test.jpg
    # content:包含你上传文件内容的File对象
    # 创建一个Fdfs_client对象
    client = Fdfs_client(self.client_conf)

    # 上传文件到fast dfs系统中
    res = client.upload_by_buffer(content.read())

    # dict
    # {
    #     'Group name': group_name,
    #     'Remote file_id': remote_file_id,
    #     'Status': 'Upload successed.',
    #     'Local file name': '',
    #     'Uploaded size': upload_size,
    #     'Storage IP': storage_ip
    # }
    if res.get('Status') != 'Upload successed.':
        # 上传失败
        raise Exception('上传文件到fast dfs失败')

    # 获取返回的文件ID
    filename = res.get('Remote file_id')
    print(type(filename))
    return filename
修改之后：

def _save(self,name,content):
    '''保存文件时使用'''
    # name:你选择上传文件的名字 test.jpg
    # content:包含你上传文件内容的File对象
    # 创建一个Fdfs_client对象
    client = Fdfs_client(self.client_conf)

    # 上传文件到fast dfs系统中
    res = client.upload_by_buffer(content.read())

    # dict
    # {
    #     'Group name': group_name,
    #     'Remote file_id': remote_file_id,
    #     'Status': 'Upload successed.',
    #     'Local file name': '',
    #     'Uploaded size': upload_size,
    #     'Storage IP': storage_ip
    # }
    if res.get('Status') != 'Upload successed.':
        # 上传失败
        raise Exception('上传文件到fast dfs失败')

    # 获取返回的文件ID
    filename = res.get('Remote file_id')
    print(type(filename))
    return filename.decode()