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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 large_size(self, as_string=True):
 """Returns a thumbnail's large size."""

        size = getattr(settings, 'USER_MEDIA_THUMB_SIZE_LARGE', (150, 150))
        if as_string:
            return u'{}x{}'.format(size[0], size[1])
        return size