class_docstr: Transformers that create new exog features from the endog or exog array
  
  Parameters
  ----------
  prefix : str or None, optional (default=None)
      The feature prefix
docstr: Get the feature prefix for when exog is a pd.DataFrame
docstr_tok: ["Get","the","feature","prefix","for","when","exog","is","a","pd.DataFrame"]
code: def _get_prefix(self):
      """Get the feature prefix for when exog is a pd.DataFrame"""
  
file_path: pmdarima/pmdarima/preprocessing/exog/base.py
imports: import pandas
  import numpy
  import abc
  from ..base import BaseTransformer
label_desc: Use image node_id 2 for calling the BaseExogFeaturizer obj's underlying member method code with example usage: obj._get_prefix() without return types