code: def test_sampling_warm_start(self, daily_univariate_ts, backend):
      m = Prophet(mcmc_samples=100, stan_backend=backend).fit(
          daily_univariate_ts.iloc[:500], show_progress=False
      )
      m2 = Prophet(mcmc_samples=100, stan_backend=backend).fit(
          daily_univariate_ts.iloc[:510],
          init=warm_start_params(m),
          show_progress=False,
      )
      assert m2.params["delta"].shape == (200, 25)
  
imports: import numpy
  import pandas
  import pytest
  from prophet import Prophet
  from prophet.utilities import warm_start_params
label_desc: Use image node_id 2 for calling the TestProphetWarmStart obj's underlying member method code with example usage: obj.test_sampling_warm_start(daily_univariate_ts, backend) without return types