parameters: (data)
return_statement: return struct.unpack('>ii', w4h4)
docstring: read the (width, height) from a PNG header
docstring_summary: read the (width, height) from a PNG header
docstring_tokens: read the ( width height ) from a PNG header
function: def _pngxy(data):
      """read the (width, height) from a PNG header"""
      ihdr = data.index(b'IHDR')
      # next 8 bytes are width/height
      w4h4 = data[ihdr+4:ihdr+12]
      return struct.unpack('>ii', w4h4)
function_tokens: def _pngxy ( data ) : ihdr = data . index ( b'IHDR' ) # next 8 bytes are width/height w4h4 = data [ ihdr + 4 : ihdr + 12 ] return struct . unpack ( '>ii' , w4h4 )