code: def single_value(cls, value, shape, pixel_scale, origin=(0.0, 0.0)):
          
          array = np.ones(shape) * value
          return cls(array, pixel_scale, origin)
docs: Creates an instance of Array and fills it with a single value
  
          Parameters
          ----------
          value: float
              The value with which the array should be filled
          shape: (int, int)
              The shape of the array
          pixel_scale: float
              The scale of a pixel in arc seconds
  
          Returns
          -------
          array: ScaledSquarePixelArray
              An array filled with a single value