code: def test_uncomment():
      assert uncomment(
          ["# line one", "#line two", "line three"], "#"
      ) == [
          "line one",
          "line two",
          "line three",
      ]
      assert uncomment(
          ["# line one", "#line two", "line three"], ""
      ) == [
          "# line one",
          "#line two",
          "line three",
      ]
  
file_path: jupytext/tests/functional/others/test_cells.py
imports: import pytest
  from nbformat.v4.nbbase import new_markdown_cell
  from jupytext.cell_reader import LightScriptCellReader, RMarkdownCellReader, paragraph_is_fully_commented, uncomment
  from jupytext.cell_to_text import RMarkdownCellExporter
label_desc: Use image node_id 3 for calling a global function with example usage: test_uncomment() without return types