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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_hash_of_dirs(directory):
 """ Recursively hash the contents of the given directory. Args: directory (str):
 The root directory we want to hash. Returns: A hash of all the contents in the directory. """

    import hashlib
    sha = hashlib.sha512()
    if not os.path.exists(directory):
        return -1

    for root, _, files in os.walk(directory):
        for name in files:
            filepath = local.path(root) / name
            if filepath.exists():
                with open(filepath, 'rb') as next_file:
                    for line in next_file:
                        sha.update(line)
    return sha.hexdigest()