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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 _freevar_argname(arg, cellvars, freevars):
 """ Get the name of the variable manipulated by a 'uses_free' instruction. Parameters arg : int The raw argument to a uses_free instruction that we want to resolve to a name. cellvars : list[str] The co_cellvars of the function for which we want to resolve `arg`. freevars : list[str] The co_freevars of the function for which we want to resolve `arg`. Notes ----- From https://docs.python.org/3.5/library/dis.html#opcode-LOAD_CLOSURE: The name of the variable is co_cellvars[i] if i is less than the length of co_cellvars. Otherwise it is co_freevars[i - len(co_cellvars)] """

    len_cellvars = len(cellvars)
    if arg < len_cellvars:
        return cellvars[arg]
    return freevars[arg - len_cellvars]