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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_apply(lib, symbol, func, chunk_range=None):
 """ Apply `func` to each chunk in lib.symbol Parameters lib: arctic library symbol: str the symbol for the given item in the DB chunk_range: None, or a range object allows you to subset the chunks by range Returns ------- generator """

    for chunk in lib.iterator(symbol, chunk_range=chunk_range):
        yield func(chunk)