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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 notes_placeholder(self):
 """ Return the notes placeholder on this notes slide, the shape that contains the actual notes text. Return |None| if no notes placeholder is present; while this is probably uncommon, it can happen if the notes master does not have a body placeholder, or if the notes placeholder has been deleted from the notes slide. """

        for placeholder in self.placeholders:
            if placeholder.placeholder_format.type == PP_PLACEHOLDER.BODY:
                return placeholder
        return None