docstr: Fourier order cannot be <= 0
docstr_tok: ["Fourier","order","can","not","be","<","=","0"]
code: def test_custom_fourier_order(self, backend):
      """Fourier order cannot be <= 0"""
      m = Prophet(stan_backend=backend)
      with pytest.raises(ValueError):
          m.add_seasonality(name="weekly", period=7, fourier_order=0)
      with pytest.raises(ValueError):
          m.add_seasonality(name="weekly", period=7, fourier_order=-1)
  
imports: import numpy
  import pandas
  import pytest
  from prophet import Prophet
  from prophet.utilities import warm_start_params
label_desc: Use image node_id 3 for calling the TestProphetCustomSeasonalComponent obj's underlying member method code with example usage: obj.test_custom_fourier_order(backend) without return types