code: def test_is_number():
      assert strings_utils.is_number("1.1")
      assert strings_utils.is_number("1.000001")
      assert strings_utils.is_number("1000001")
      assert strings_utils.is_number("Nan")
      assert strings_utils.is_number("NaN")
      assert strings_utils.is_number(1)
      assert strings_utils.is_number(1.1)
      assert not strings_utils.is_number("NaNaaa")
  
file_path: ludwig/tests/ludwig/utils/test_strings_utils.py
imports: from collections import defaultdict
  import numpy
  import pandas
  import pytest
  from ludwig.schema.features.preprocessing.text import TextPreprocessingConfig
  from ludwig.utils import strings_utils
label_desc: Use image node_id 1 for calling a global function with example usage: test_is_number() without return types