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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 simplify_textboxes(miner, textbox_getter):
 """Extract only limited content from text boxes We do this to save memory and ensure that our objects are pickleable. """

    for box in textbox_getter(miner):
        first_line = box._objs[0]
        first_char = first_line._objs[0]

        visible = first_char.rendermode != 3
        corrupt = first_char.get_text() == '\ufffd'
        yield TextboxInfo(box.bbox, visible, corrupt)