import responses
import requests
from urllib.request import urlopen

@responses.activate
def test_request_img():
    url_img = 'http://falseurlf.com'
    responses.add(
        method=responses.GET,
        url=url_img,
        body='111',
    )
    resp = urlopen(url_img)  #not work
    #resp = requests.get(url_img) #work
    return resp
resp = test_request_img()

---------------------------------------------------------------------------
RemoteDisconnected                        Traceback (most recent call last)
<ipython-input-8-2105ab8f8843> in <module>
     14     #resp = requests.get(url_img) #work
     15     return resp
---> 16 resp = test_request_img()

<string> in wrapper()

<ipython-input-8-2105ab8f8843> in test_request_img()
     11         body='111',
     12     )
---> 13     resp = urlopen(url_img)  #not work
     14     #resp = requests.get(url_img) #work
     15     return resp

~/anaconda3/lib/python3.8/urllib/request.py in urlopen(url, data, timeout, cafile, capath, cadefault, context)
    220     else:
    221         opener = _opener
--> 222     return opener.open(url, data, timeout)
    223
    224 def install_opener(opener):

~/anaconda3/lib/python3.8/urllib/request.py in open(self, fullurl, data, timeout)
    523
    524         sys.audit('urllib.Request', req.full_url, req.data, req.headers, req.get_method())
--> 525         response = self._open(req, data)
    526
    527         # post-process response

~/anaconda3/lib/python3.8/urllib/request.py in _open(self, req, data)
    540
    541         protocol = req.type
--> 542         result = self._call_chain(self.handle_open, protocol, protocol +
    543                                   '_open', req)
    544         if result:

~/anaconda3/lib/python3.8/urllib/request.py in _call_chain(self, chain, kind, meth_name, *args)
    500         for handler in handlers:
    501             func = getattr(handler, meth_name)
--> 502             result = func(*args)
    503             if result is not None:
    504                 return result

~/anaconda3/lib/python3.8/urllib/request.py in http_open(self, req)
   1377
   1378     def http_open(self, req):
-> 1379         return self.do_open(http.client.HTTPConnection, req)
   1380
   1381     http_request = AbstractHTTPHandler.do_request_

~/anaconda3/lib/python3.8/urllib/request.py in do_open(self, http_class, req, **http_conn_args)
   1352             except OSError as err: # timeout error
   1353                 raise URLError(err)
-> 1354             r = h.getresponse()
   1355         except:
   1356             h.close()

~/anaconda3/lib/python3.8/http/client.py in getresponse(self)
   1330         try:
   1331             try:
-> 1332                 response.begin()
   1333             except ConnectionError:
   1334                 self.close()

~/anaconda3/lib/python3.8/http/client.py in begin(self)
    301         # read until we get a non-100 response
    302         while True:
--> 303             version, status, reason = self._read_status()
    304             if status != CONTINUE:
    305                 break

~/anaconda3/lib/python3.8/http/client.py in _read_status(self)
    270             # Presumably, the server closed the connection before
    271             # sending a valid response.
--> 272             raise RemoteDisconnected("Remote end closed connection without"
    273                                      " response")
    274         try:

RemoteDisconnected: Remote end closed connection without response

import responses
import requests
from urllib.request import urlopen

@responses.activate
def test_request_img():
    url_img = 'http://falseurlf.com'
    responses.add(
        method=responses.GET,
        url=url_img,
        body='111',
    )
    #resp = urlopen(url_img)  #not work
    resp = requests.get(url_img) #work
    return resp
resp = test_request_img()
print(resp.text)