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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 _reference_info(references):
 """Get information about document references. Helper for :meth:`~.firestore_v1beta1.client.Client.get_all`. Args: references. Returns: * fully-qualified documents paths for each reference in ``references`` * a mapping from the paths to the original reference. (If multiple ``references`` contains multiple references to the same document, that key will be overwritten in the result.) """

    document_paths = []
    reference_map = {}
    for reference in references:
        doc_path = reference._document_path
        document_paths.append(doc_path)
        reference_map[doc_path] = reference

    return document_paths, reference_map