class_docstr: Test behaviour of the from_pandas method
docstr: Every columns that is in the data should become a node in the learned structure
docstr_tok: ["Every","columns","that","is","in","the","data","should","become","a","node","in","the","learned","structure"]
code: def test_all_columns_in_structure(self, train_data_idx):
      """Every columns that is in the data should become a node in the learned structure"""
  
      g = from_pandas(train_data_idx)
      assert len(g.nodes) == len(train_data_idx.columns)
  
imports: import logging
  import networkx
  import numpy
  import pandas
  import pytest
  import scipy.optimize
  from mock import patch
  from causalnex.structure import StructureModel
  from causalnex.structure.data_generators import generate_binary_data, generate_binary_dataframe, generate_continuous_dataframe, generate_count_dataframe, generate_structure
  from causalnex.structure.pytorch.notears import from_numpy, from_pandas
label_desc: Use image node_id 1 for calling the TestFromPandas obj's underlying member method code with example usage: obj.test_all_columns_in_structure(train_data_idx) without return types