old_contents: import os
  
  
  def envvar(name, default):
      """Create callable environment variable getter
  
      :param str name: Name of environment variable
      :param default: Default value to return in case it isn't defined
      """
      return lambda: os.environ.get(name, default)
  
  
  def flag_ennvar(name):
      return os.environ.get(name) == '1'
  
new_contents: """Extensions for use with click options"""
  
  import os
  
  
  def envvar(name, default):
      """Create callable environment variable getter
  
      :param str name: Name of environment variable
      :param default: Default value to return in case it isn't defined
      """
      return lambda: os.environ.get(name, default)
  
  
  def flag_ennvar(name):
      return os.environ.get(name) == '1'
  
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