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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 make_directory_if_needed(directory_path):
 """ Make the directory path, if needed. """

    if os.path.exists(directory_path):
        if not os.path.isdir(directory_path):
            raise OSError("Path is not a directory:", directory_path)
    else:
        os.makedirs(directory_path)