old_contents: # coding=utf-8
  # -------------------------------------------------------------------------------
  # Author: Alexandre Manhaes Savio <alexsavio@gmail.com>
  # Grupo de Inteligencia Computational <www.ehu.es/ccwintco>
  # Universidad del Pais Vasco UPV/EHU
  #
  # 2015, Alexandre Manhaes Savio
  # Use this at your own risk!
  # -------------------------------------------------------------------------------
  
  import os
  import sys
  import shutil
  import subprocess
  import os.path      as op
  from   subprocess   import CalledProcessError
  import logging
  
  log = logging.getLogger(__name__)
  
  
  def which(program):
      """Returns the absolute path of the given CLI program name."""
      if (sys.version_info > (3, 0)):
          return which_py3(program)
      else:
          # Python 2 code in this block
          return which_py2(program)
  
  
  def which_py3(program):
      return shutil.which(program)
  
  
  def which_py2(program):
      def is_exe(fpath):
          return os.path.isfile(fpath) and os.access(fpath, os.X_OK)
  
      fpath, fname = os.path.split(program)
      if fpath:
          if is_exe(program):
              return program
      else:
          for path in os.environ["PATH"].split(os.pathsep):
              path = path.strip('"')
              exe_file = os.path.join(path, program)
              if is_exe(exe_file):
                  return exe_file
  
      return None
  
  
  def call_command(cmd_name, args_strings):
      """Call CLI command with arguments and returns its return value.
  
      Parameters
      ----------
      cmd_name: str
          Command name or full path to the binary file.
  
      arg_strings: str
          Argument strings list.
  
      Returns
      -------
      return_value
          Command return value.
      """
      if not op.isabs(cmd_name):
          cmd_fullpath = which(cmd_name)
      else:
          cmd_fullpath = cmd_name
  
      try:
          cmd_line = [cmd_fullpath] + args_strings
  
          log.info('Calling: {}.'.format(cmd_line))
          retval = subprocess.check_call(cmd_line)
      except CalledProcessError as ce:
          log.exception("Error calling command {} with arguments: "
                        "{} \n With return code: {}".format(cmd_name, args_strings,
                                                            ce.returncode))
          raise
      else:
          return retval
  
new_contents: # coding=utf-8
  # -------------------------------------------------------------------------------
  # Author: Alexandre Manhaes Savio <alexsavio@gmail.com>
  # Grupo de Inteligencia Computational <www.ehu.es/ccwintco>
  # Universidad del Pais Vasco UPV/EHU
  #
  # 2015, Alexandre Manhaes Savio
  # Use this at your own risk!
  # -------------------------------------------------------------------------------
  
  import os
  import sys
  import shutil
  import subprocess
  import os.path      as op
  from   subprocess   import CalledProcessError
  import logging
  
  log = logging.getLogger(__name__)
  
  
  
  def is_exe(fpath):
      """Return True if fpath is an executable file path.
  
      Parameters
      ----------
      fpath: str
          File path
  
      Returns
      -------
      is_executable: bool
      """
      return op.isfile(fpath) and os.access(fpath, os.X_OK)
  
  
  def which(program):
      """Returns the absolute path of the given CLI program name."""
      if (sys.version_info > (3, 0)):
          return which_py3(program)
      else:
          # Python 2 code in this block
          return which_py2(program)
  
  
  def which_py3(program):
      return shutil.which(program)
  
  
  def which_py2(program):
      fpath, fname = os.path.split(program)
      if fpath:
          if is_exe(program):
              return program
      else:
          for path in os.environ["PATH"].split(os.pathsep):
              path = path.strip('"')
              exe_file = os.path.join(path, program)
              if is_exe(exe_file):
                  return exe_file
  
      return None
  
  
  def call_command(cmd_name, args_strings):
      """Call CLI command with arguments and returns its return value.
  
      Parameters
      ----------
      cmd_name: str
          Command name or full path to the binary file.
  
      arg_strings: str
          Argument strings list.
  
      Returns
      -------
      return_value
          Command return value.
      """
      if not op.isabs(cmd_name):
          cmd_fullpath = which(cmd_name)
      else:
          cmd_fullpath = cmd_name
  
      try:
          cmd_line = [cmd_fullpath] + args_strings
  
          log.info('Calling: {}.'.format(cmd_line))
          retval = subprocess.check_call(cmd_line)
      except CalledProcessError as ce:
          log.exception("Error calling command {} with arguments: "
                        "{} \n With return code: {}".format(cmd_name, args_strings,
                                                            ce.returncode))
          raise
      else:
          return retval
  
subject: Add is_exe to commands.py