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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 get_and_check_project(valid_vcs_rules, source_url):
 """Given vcs rules and a source_url, return the project. The project is in the path, but is the repo name. `releases/mozilla-beta` is the path; `mozilla-beta` is the project. Args: valid_vcs_rules (tuple of frozendicts):
 the valid vcs rules, per ``match_url_regex``. source_url (str):
 the source url to find the project for. Raises: RuntimeError: on failure to find the project. Returns: str: the project. """

    project_path = match_url_regex(valid_vcs_rules, source_url, match_url_path_callback)
    if project_path is None:
        raise ValueError("Unknown repo for source url {}!".format(source_url))
    project = project_path.split('/')[-1]
    return project