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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 _release_and_issues(changelog, branch, release_type):
 """ Return most recent branch-appropriate release, if any, and its contents. :param dict changelog: Changelog contents, as returned by ``releases.util.parse_changelog``. :param str branch: Branch name. :param release_type: Member of `Release`, e.g. `Release.FEATURE`. :returns: Two-tuple of release (``str``) and issues (``list`` of issue numbers.) If there is no latest release for the given branch (e.g. if it's a feature or master branch), it will be ``None``. """

    # Bugfix lines just use the branch to find issues
    bucket = branch
    # Features need a bit more logic
    if release_type is Release.FEATURE:
        bucket = _latest_feature_bucket(changelog)
    # Issues is simply what's in the bucket
    issues = changelog[bucket]
    # Latest release is undefined for feature lines
    release = None
    # And requires scanning changelog, for bugfix lines
    if release_type is Release.BUGFIX:
        versions = [text_type(x) for x in _versions_from_changelog(changelog)]
        release = [x for x in versions if x.startswith(bucket)][-1]
    return release, issues