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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 _is_enlargement(locator, global_index):
 """Determine if a locator will enlarge the global index. Enlargement happens when you trying to locate using labels isn't in the original index. In other words, enlargement == adding NaNs ! """

    if (
        is_list_like(locator)
        and not is_slice(locator)
        and len(locator) > 0
        and not is_boolean_array(locator)
        and (isinstance(locator, type(global_index[0])) and locator not in global_index)
    ):
        n_diff_elems = len(pandas.Index(locator).difference(global_index))
        is_enlargement_boolean = n_diff_elems > 0
        return is_enlargement_boolean
    return False