docstr: Sometimes we don't need data inside Data like class, so we populate it once and only when necessary
docstr_tok: ["Sometimes","we","do","n't","need","data","inside","Data","like","class",",","so","we","populate","it","once","and","only","when","necessary"]
code: def _lazy_evaluation(self):
      """Sometimes we don't need data inside Data like class, so we populate it once and only when necessary"""
      if self._data is None:
          if self._is_map:
              self._data = pd.DataFrame(
                  (
                      np.random.randn(self._num_of_rows, 2) / [50, 50]
                      + [37.76, -122.4]
                  ),
                  columns=["lat", "lon"],
              )
          else:
              random.seed(0)
              self._data = self._random_data()
  
file_path: streamlit/lib/tests/streamlit/snowpark_mocks.py
imports: import random
  from typing import List, Union
  import numpy
  import pandas
label_desc: Use image node_id 5 for calling the _SnowparkDataLikeBaseClass obj's underlying member method code with example usage: obj._lazy_evaluation() without return types