code: def test_compress_formats():
      assert (
          short_form_multiple_formats([{"extension": ".ipynb"}])
          == "ipynb"
      )
      assert short_form_multiple_formats("ipynb") == "ipynb"
      assert (
          short_form_multiple_formats(
              [{"extension": ".ipynb"}, {"extension": ".md"}]
          )
          == "ipynb,md"
      )
      assert (
          short_form_multiple_formats(
              [
                  {"extension": ".ipynb"},
                  {"extension": ".py", "format_name": "light"},
              ]
          )
          == "ipynb,py:light"
      )
      assert (
          short_form_multiple_formats(
              [
                  {"extension": ".ipynb"},
                  {"extension": ".py", "format_name": "light"},
                  {"extension": ".md", "comment_magics": True},
              ]
          )
          == "ipynb,py:light,md"
      )
      assert (
          short_form_multiple_formats(
              [
                  {
                      "extension": ".py",
                      "suffix": ".pct",
                      "format_name": "percent",
                  }
              ]
          )
          == ".pct.py:percent"
      )
  
imports: import pytest
  from nbformat.v4.nbbase import new_notebook
  import jupytext
  from jupytext.compare import compare
  from jupytext.formats import JupytextFormatError, divine_format, get_format_implementation, guess_format, long_form_multiple_formats, read_format_from_metadata, rearrange_jupytext_metadata, short_form_multiple_formats, update_jupytext_formats_metadata, validate_one_format
label_desc: Use image node_id 18 for calling a global function with example usage: test_compress_formats() without return types