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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 IHDR(self):
 """ IHDR chunk in PNG image """

        match = lambda chunk: chunk.type_name == PNG_CHUNK_TYPE.IHDR  # noqa
        IHDR = self._find_first(match)
        if IHDR is None:
            raise InvalidImageStreamError('no IHDR chunk in PNG image')
        return IHDR