A util function to check whether a given URL exists or not

check_url_exists.py

import urllib.request

# NOTE: Python 3.6+ installations on macOS require an extra step to work with
# https links due to certificate access issues.

# Here is a snippet from the release notes.

# This package includes its own private copy of OpenSSL 1.1.1.
# The trust certificates in system and user keychains managed by the Keychain Access application and the security
# command line utility are not used as defaults by the Python ssl module.  A sample command script is included
# in /Applications/Python 3.9 to install a curated bundle of default root certificates from the third-party
# certifi package (https://pypi.org/project/certifi/).  Double-click on Install Certificates to run it.

# See https://www.python.org/downloads/release/python-360/

def check_url_exists(url:str) -> bool:
    """
    Returs True if the given link exists and accessible, False otherwise
    """

    # Just checking whether an URL exists or not.
    # The default method type is GET which fetches the data associated
    # with the URL as well. HEAD method simply fetches only the header
    # which is enough to for this function. Hence setting method to HEAD
    # in the request object
    # See https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods

    request = urllib.request.Request(url, method='HEAD')

    try:
        with urllib.request.urlopen(request) as response:
            # some helpful information to remember
            # response.info() returns an instance of mimetools.Message
            # For http response, this carries the header information
            # print(response.info())
            # response.read() will return the data attached to the 
            # print(response.read())
            return True
    except(urllib.request.HTTPError):
        # Checking for HTTPError only.
        # A different error will be raised (e.g. socket error) if there
        # is any network error.
        return False

# Tested with Python3.6+ versions
# print(check_url_exists("https://unsplash.com/photos/-zvx4EoPRDw"))