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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 get_image_as_buffer(self, output=None):
 """Get the current image shown in the viewer, with any overlaid graphics, in a IO buffer with channels as needed and ordered by the back end widget. This can be overridden by subclasses. Parameters output : a file IO-like object or None open python IO descriptor or None to have one created Returns ------- buffer : file IO-like object This will be the one passed in, unless `output` is None in which case a BytesIO obejct is returned """

        obuf = output
        if obuf is None:
            obuf = BytesIO()

        arr8 = self.get_image_as_array()
        if not hasattr(arr8, 'tobytes'):
            # older versions of numpy
            obuf.write(arr8.tostring(order='C'))
        else:
            obuf.write(arr8.tobytes(order='C'))

        ## if output is not None:
        ##     return None
        return obuf