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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 get_select_items(items):
 """Return list of possible select items."""

    option_items = list()
    for item in items:
        if isinstance(item, dict) and defs.VALUE in item and defs.LABEL in item:
            option_items.append(item[defs.VALUE])
        else:
            raise exceptions.ParametersFieldError(item, "a dictionary with {} and {}"
                                                  .format(defs.LABEL, defs.VALUE))
    return option_items