code: def read_frame(
      directory,
      filename,
      extension,
      separator,
      index_col=None,
      squeeze=False,
  ):
      r"""Read a delimiter-separated file into a data frame.
  
      Parameters
      ----------
      directory : str
          Full directory specification.
      filename : str
          Name of the file to read, excluding the ``extension``.
      extension : str
          File name extension, e.g., ``csv``.
      separator : str
          The delimiter between fields in the file.
      index_col : str, optional
          Column to use as the row labels in the dataframe.
      squeeze : bool, optional
          If the data contains only one column, then return a pandas Series.
  
      Returns
      -------
      df : pandas.DataFrame
          The pandas dataframe loaded from the file location. If the file
          cannot be located, then ``None`` is returned.
  
      """
      file_only = PSEP.join([filename, extension])
      file_all = SSEP.join([directory, file_only])
      logger.info("Loading data from %s", file_all)
      try:
          df = pd.read_csv(
              file_all,
              sep=separator,
              index_col=index_col,
              squeeze=squeeze,
              low_memory=False,
          )
      except:
          df = pd.DataFrame()
          logger.info("Could not find or access %s", file_all)
      return df
  
file_path: AlphaPy/alphapy/frame.py
imports: from alphapy.globals import PSEP, SSEP, USEP
  from alphapy.globals import TAG_ID
  import logging
  import pandas
label_desc: Use image node_id 2 for calling a global function with example usage: read_frame(directory, filename, extension, separator, index_col, squeeze) and returns: df