def read_header(self):
        """ Read header and return a Python dictionary of key:value pairs
        """

        self.header = {}

        for key, val in self.h5['data'].attrs.items():
            if six.PY3:
                key = bytes(key, 'ascii')
            if key == b'src_raj':
                self.header[key] = Angle(val, unit='hr')
            elif key == b'src_dej':
                self.header[key] = Angle(val, unit='deg')
            else:
                self.header[key] = val

        return self.header
Read header and return a Python dictionary of key:value pairs