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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 initialize_repository(path, spor_dir='.spor'):
 """Initialize a spor repository in `path` if one doesn't already exist. Args: path: Path to any file or directory within the repository. spor_dir: The name of the directory containing spor data. Returns: A `Repository` instance. Raises: ValueError: A repository already exists at `path`. """

    path = pathlib.Path(path)
    spor_path = path / spor_dir
    if spor_path.exists():
        raise ValueError('spor directory already exists: {}'.format(spor_path))
    spor_path.mkdir()

    return Repository(path, spor_dir)