keras/src/layers/rnn/conv_lstm.py/ConvLSTMCell/get_initial_state
class ConvLSTMCell:    def get_initial_state(self, batch_size=None):
        if self.data_format == "channels_last":
            input_shape = (batch_size,) + self.spatial_dims + (self.input_dim,)
        else:
            input_shape = (batch_size, self.input_dim) + self.spatial_dims
        state_shape = self.compute_output_shape(input_shape)[0]
        return [
            ops.zeros(state_shape, dtype=self.compute_dtype),
            ops.zeros(state_shape, dtype=self.compute_dtype),
        ]