old_contents: # -*- coding: utf-8 -*-
  
  from __future__ import unicode_literals
  
  
  __all__ = ('is_snake',)
  
  
  def is_snake(word):
      if not word.isalpha():
          raise ValueError("String '{}' is not a word")
      if word.lower() == 'python':
          return True
      if word.lower() == 'питон':
          return True
      return False
  
  
  def _parse_args(args=None):
      """Parse command line arguments"""
      parser = argparse.ArgumentParser(description='Check if animal is snake')
      parser.add_argument('word', help='an animal to check')
      namespace = parser.parse_args()
      return namespace
  
  
  def main():
      """Entry-point for ser module"""
      word = _parse_args().word
      if is_snake(word):
          print('{} is a snake'.format(word))
          return
      print('{} is not a snake'.format(word))
  
  
  def plot():
      """Plot a snake"""
      import math
      import matplotlib.pyplot as plt
  
      x = [i / 10 for i in range(100)]
      plt.plot(x, [math.sin(a) for a in x])
      plt.show()
      plt.close()
  
new_contents: # -*- coding: utf-8 -*-
  
  from __future__ import unicode_literals
  
  
  __all__ = ('is_snake',)
  
  
  def is_snake(word):
      """Checks if an animal is a snake
  
      Parameters
      ----------
      word : str
          Animal name
  
      Returns
      -------
      bool
  
      Example
      -------
      Check if a bear is a snake
  
      >>> from ser.snake import is_snake
      >>>
      >>> if is_snake('bear'):
      ...     print('Shhhh')
      ... else:
      ...     print('Argh')
      Argh
  
      """
      if not word.isalpha():
          raise ValueError("String '{}' is not a word")
      if word.lower() == 'python':
          return True
      if word.lower() == 'питон':
          return True
      return False
  
  
  def _parse_args(args=None):
      """Parse command line arguments"""
      parser = argparse.ArgumentParser(description='Check if animal is snake')
      parser.add_argument('word', help='an animal to check')
      namespace = parser.parse_args()
      return namespace
  
  
  def main():
      """Entry-point for ser module"""
      word = _parse_args().word
      if is_snake(word):
          print('{} is a snake'.format(word))
          return
      print('{} is not a snake'.format(word))
  
  
  def plot():
      """Plot a snake"""
      import math
      import matplotlib.pyplot as plt
  
      x = [i / 10 for i in range(100)]
      plt.plot(x, [math.sin(a) for a in x])
      plt.show()
      plt.close()
  
subject: Add doctest to the sample project