docs: def as_data_frame(self, **kwargs):
          """
          Return information for all Files tracked in the Layout as a pandas
          DataFrame.
  
          Args:
              kwargs: Optional keyword arguments passed on to get(). This allows
                  one to easily select only a subset of files for export.
          Returns:
              A pandas DataFrame, where each row is a file, and each column is
                  a tracked entity. NaNs are injected whenever a file has no
                  value for a given attribute.
          """
          try:
              import pandas as pd
          except ImportError:
              raise ImportError("What are you doing trying to export a Layout "
                                "as a pandas DataFrame when you don't have "
                                "pandas installed? Eh? Eh?")
          if kwargs:
              files = self.get(return_type='obj', **kwargs)
          else:
              files = self.files.values()
          data = pd.DataFrame.from_records([f.entities for f in files])
          data.insert(0, 'path', [f.path for f in files])
          return data