Calculates the size of an integration (cross + auto) in bytes

def calc_intsize(self):
        """ Calculates the size of an integration (cross + auto) in bytes
        """

        # assume first cross blob starts after headxml and second is one int of bytes later
        for k in self.binarychunks.iterkeys():
            if int(k.split('/')[3]) == 1 and 'cross' in k.split('/')[-1]:
                headsize = self.binarychunks[k]
                break
        for k in self.binarychunks.iterkeys():
            if int(k.split('/')[3]) == 2 and 'cross' in k.split('/')[-1]:
                intsize = self.binarychunks[k] - headsize
                break

        return (headsize, intsize)