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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 table( table_name=None, cache=False, cache_scope=_CS_FOREVER, copy_col=True):
 """ Decorates functions that return DataFrames. Decorator version of `add_table`. Table name defaults to name of function. The function's argument names and keyword argument values will be matched to registered variables when the function needs to be evaluated by Orca. The argument name "iter_var" may be used to have the current iteration variable injected. """

    def decorator(func):
        if table_name:
            name = table_name
        else:
            name = func.__name__
        add_table(
            name, func, cache=cache, cache_scope=cache_scope,
            copy_col=copy_col)
        return func
    return decorator