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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 set_size(self, size):
 """ Set the size of the map in pixels This is an expensive operation, do only when absolutely needed. :param size: (width, height) pixel size of camera/view of the group """

        buffer_size = self._calculate_zoom_buffer_size(size, self._zoom_level)
        self._size = size
        self._initialize_buffers(buffer_size)