code: def test_read_csv(pdf, monkeypatch, tmpdir):
      # Write to buffer
      fpath = TEST_BUCKET + "test_csv_reader.csv"
      buffer = pdf.to_csv(index=False)
  
      def mock_open(*args, **kwargs):
          return io.BytesIO(buffer.encode())
  
      def mock_size(*args):
          return len(buffer.encode())
  
      monkeypatch.setattr(gcsfs.core.GCSFileSystem, "open", mock_open)
      monkeypatch.setattr(gcsfs.core.GCSFileSystem, "size", mock_size)
  
      # Test read from explicit path.
      # Since we are monkey-patching, we cannot use
      # use_python_file_object=True, because the pyarrow
      # `open_input_file` command will fail (since it doesn't
      # use the monkey-patched `open` definition)
      got = cudf.read_csv(
          f"gcs://{fpath}", use_python_file_object=False
      )
      assert_eq(pdf, got)
  
      # AbstractBufferedFile -> PythonFile conversion
      # will work fine with the monkey-patched FS if we
      # pass in an fsspec file object
      fs = gcsfs.core.GCSFileSystem()
      with fs.open(f"gcs://{fpath}") as f:
          got = cudf.read_csv(f)
      assert_eq(pdf, got)
  
file_path: cudf/python/cudf/cudf/tests/test_gcs.py
imports: import io
  import os
  import numpy
  import pandas
  import pytest
  import cudf
  from cudf.testing._utils import assert_eq
label_desc: Use image node_id 2 for calling a global function with example usage: test_read_csv(pdf, monkeypatch, tmpdir) and returns: io, len