code: def head_file(fileName, line_count, path="samples"):
      assert line_count > 0
      fileLines = get_file_lines(os.path.join(path, fileName))
      return fileLines[0:line_count]
  
imports: import csv
  import os
  import shutil
  import subprocess
  import tempfile
  import unittest
  import matplotlib
  from six.moves import xrange
  from pyalgotrade import dataseries
label_desc: Use image node_id 7 for calling a global function with example usage: head_file(fileName, line_count, path) and returns: fileLines