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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def requestCheckRegularDocker(origAppliance, registryName, imageName, tag):
 """ Checks to see if an image exists using the requests library. URL is based on the docker v2 schema described here: https://docs.docker.com/registry/spec/manifest-v2-2/ This has the following format: https://{websitehostname}.io/v2/{repo}/manifests/{tag} Does not work with the official (docker.io) site, because they require an OAuth token, so a separate check is done for docker.io images. :param str origAppliance: The full url of the docker image originally specified by the user (or the default). e.g. "quay.io/ucsc_cgl/toil:latest" :param str registryName: The url of a docker image's registry. e.g. "quay.io" :param str imageName: The image, including path and excluding the tag. e.g. "ucsc_cgl/toil" :param str tag: The tag used at that docker image's registry. e.g. "latest" :return: Return True if match found. Raise otherwise. """

    ioURL = 'https://{webhost}/v2/{pathName}/manifests/{tag}' \
              ''.format(webhost=registryName, pathName=imageName, tag=tag)
    response = requests.head(ioURL)
    if not response.ok:
        raise ApplianceImageNotFound(origAppliance, ioURL, response.status_code)
    else:
        return origAppliance