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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 decompile(f):
 """ Decompile a function. Parameters f : function The function to decompile. Returns ------- ast : ast.FunctionDef A FunctionDef node that compiles to f. """

    co = f.__code__
    args, kwonly, varargs, varkwargs = paramnames(co)
    annotations = f.__annotations__ or {}
    defaults = list(f.__defaults__ or ())
    kw_defaults = f.__kwdefaults__ or {}

    if f.__name__ == '<lambda>':
        node = ast.Lambda
        body = pycode_to_body(co, DecompilationContext(in_lambda=True))[0]
        extra_kwargs = {}
    else:
        node = ast.FunctionDef
        body = pycode_to_body(co, DecompilationContext(in_function_block=True))
        extra_kwargs = {
            'decorator_list': [],
            'returns': annotations.get('return')
        }

    return node(
        name=f.__name__,
        args=make_function_arguments(
            args=args,
            kwonly=kwonly,
            varargs=varargs,
            varkwargs=varkwargs,
            defaults=defaults,
            kw_defaults=kw_defaults,
            annotations=annotations,
        ),
        body=body,
        **extra_kwargs
    )