text: #!/usr/bin/env python3
  # vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4
  from __future__ import print_function
  
  import sys
  
  
  def indent(line):
      if line == '':
          return None
      end = 0
      for c in line:
          end += 1
          if " \t" not in c:
              return line[:end]
      return line
  
  
  start_block = False
  filter_indent = None
  
  for line in open(sys.argv[1]):
  
      if line == '\n':
          continue
  
      if filter_indent:
          if line.startswith(filter_indent):
              continue
          else:
              filter_indent = None
  
      if line.strip().startswith('.. '):
          start_block = True
          continue
  
      if line.endswith('::\n'):
          start_block = True
          continue
  
      if start_block:
          filter_indent = indent(line)
          start_block = False
          continue
  
      sys.stdout.write(line)
  