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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 github(cls, user, repo):
 """Creates an `Scm` for a github repo. :param string user: The github user or organization name the repo is hosted under. :param string repo: The repository name. :returns: An `Scm` representing the github repo. """

    # For the url format, see: http://maven.apache.org/scm/git.html
    params = dict(user=user, repo=repo)
    connection = 'scm:git:git@github.com:{user}/{repo}.git'.format(**params)
    url = 'https://github.com/{user}/{repo}'.format(**params)
    return cls(connection=connection, developer_connection=connection, url=url)