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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 read_args_tool(toolkey, example_parameters, tool_add_args=None):
 """Read args for single tool. """

    import scanpy as sc
    p = default_tool_argparser(help(toolkey), example_parameters)
    if tool_add_args is None:
        p = add_args(p)
    else:
        p = tool_add_args(p)
    args = vars(p.parse_args())
    args = settings.process_args(args)
    return args