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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 add_field(field, func, dict_sequence):
 """ Apply given function to the record and store result in given field of current record. Do nothing if record already contains given field. """

    for item in dict_sequence:
        if field not in item:
            item[field] = func(item)
        yield item