new_contents: # -*- coding: utf-8 -*-
  """
  This module contains functions to preprocess the input files to compute
  a Finite Element Analysis.
  
  """
  from __future__ import division, print_function
  import sys
  import numpy as np
  
  
  def readin(folder=""):
      """Read the input files"""
      nodes = np.loadtxt(folder + 'nodes.txt', ndmin=2)
      mats = np.loadtxt(folder + 'mater.txt', ndmin=2)
      elements = np.loadtxt(folder + 'eles.txt', ndmin=2, dtype=np.int)
      loads = np.loadtxt(folder + 'loads.txt', ndmin=2)
  
      return nodes, mats, elements, loads
  
  
  def echomod(nodes, mats, elements, loads, folder=""):
      """Create echoes of the model input files"""
      np.savetxt(folder + "KNODES.txt", nodes, fmt='%5.2f', delimiter=' ')
      np.savetxt(folder + "KMATES.txt", mats, fmt='%5.2f', delimiter=' ')
      np.savetxt(folder + "KELEMS.txt", elements, fmt='%d', delimiter=' ')
      np.savetxt(folder + "KLOADS.txt", loads, fmt='%5.2f', delimiter=' ')
  
  
  def initial_params():
      """Read initial parameters for the simulation
      
      The parameters to be read are:
  
      - folder: location of the input files.
      - name: name for the output files (if echo is True).
      - echo: echo output files.
      """
      # Check Python version
      version = sys.version_info.major
      if version == 3:
          global raw_input
          raw_input = input
      elif version == 2:
          pass
      else:
          raise ValueError("You should use Python 2.x at least!")
  
      # Try to run with easygui
      try:
          import easygui
          folder = easygui.diropenbox(title="Folder for the job") + "/"
      except:
          folder = raw_input('Enter folder (empty for the current one): ')
  
      return folder
subject: Fix raw_input bug