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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 load_vasp_summary( filename ):
 """ Reads a `vasp_summary.yaml` format YAML file and returns a dictionary of dictionaries. Each YAML document in the file corresponds to one sub-dictionary, with the corresponding top-level key given by the `title` value. Example: The file: --- title: foo data: foo_data --- title: bar data: bar_data is converted to the dictionary { 'foo': { 'title': 'foo', 'data': 'foo_data' }, 'bar': { 'title': 'bar', 'data': 'bar_data' } } Args: filename (str):
 File path for the `vasp_summary.yaml` file. Returns: each as dictionaries.a """

    with open( filename, 'r' ) as stream:
        docs = yaml.load_all( stream, Loader=yaml.SafeLoader )
        data = { d['title']: d for d in docs }
    return data