请问 这个代码哪里有问题，报的这个错事什么意思，怎么修改
import pandas_alive as pda
covid_df = pda.load_dataset('covid19.csv')
covid_df.plot_animated(filename='examples/example-barv-chart.gif',orientation='v')
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/urllib/request.py", line 1319, in do_open
h.request(req.get_method(), req.selector, req.data, headers,
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/http/client.py", line 1230, in request
self._send_request(method, url, body, headers, encode_chunked)
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/http/client.py", line 1276, in _send_request
self.endheaders(body, encode_chunked=encode_chunked)
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/http/client.py", line 1225, in endheaders
self._send_output(message_body, encode_chunked=encode_chunked)
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/http/client.py", line 1004, in _send_output
self.send(msg)
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/http/client.py", line 944, in send
self.connect()
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/http/client.py", line 1392, in connect
super().connect()
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/http/client.py", line 915, in connect
self.sock = self._create_connection(
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/socket.py", line 808, in create_connection
raise err
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/socket.py", line 796, in create_connection
sock.connect(sa)
ConnectionRefusedError: [Errno 61] Connection refused
