


Why NameResolutionError(self.host, self, e) from e and how to solve it
The reason for the error
NameResolutionError(self.host, self, e) from e is the exception type in the urllib3 library, The cause of this error is a DNS resolution failure, that is, the hostname or IP address that was attempted to be resolved could not be found. This may be caused by the entered URL address being incorrect, or the DNSserver being temporarily unavailable.
How to solve
There may be several ways to solve this error:
Check whether the entered URL address is correct and make sure it is accessible
Make sure the DNS server is available, you can try using the "ping" command on the command line to Test whether the DNS server is available
Try using the IP address instead of the hostname to access the website
If you are in a proxy environment, check whether the proxy configuration is correct.
Check the network connection to make sure the localhost can access the Internet.
Usage example
Yes, the following is a sample code that uses the urllib3 library to access the URL and handle the NameResolutionError exception:
import urllib3 Http = urllib3.PoolManager() try: response = http.request('GET', 'http://example.com') print(response.data) except urllib3.exceptions.NewConnectionError as e: print("Name resolution error: ", e)
In this example, we use the PoolManager() method of the urllib3 library to create an HTTP connection pool, and then use the request() method to issue a GET request. If a NameResolutionError exception occurs, it will be caught and error information printed.
Note: When using http.request(), if the entered url is incorrect or inaccessible, errors such as MaxRetryError and NewConnectionError will be thrown, and corresponding handling is required.
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