code: def test_r_glm_covariates():
      dataset = sm.datasets.get_rdataset("cars").data
      genotype_df = dataset.loc[:, ["speed"]]
      phenotype_df = dataset.loc[:, ["dist"]]
      phenotype_df.loc[0, "dist"] = np.nan
      covariate_df = pd.DataFrame(
          {"intercept": np.ones(genotype_df.shape[0])}
      )
      assert_glow_equals_golden(
          genotype_df, phenotype_df, covariate_df, add_intercept=False
      )
  
imports: import functions
  import numpy
  import statsmodels.api
  import pandas
  import glow.gwas.functions
  import glow.gwas.lin_reg
  import pytest
label_desc: Use image node_id 10 for calling a global function with example usage: test_r_glm_covariates() without return types