new_contents: #!/usr/bin/env python3
  
  import glob
  
  SEPARATOR_LINES = ('//\n', '\n')
  for header in sorted(glob.glob('include/gemmi/*.hpp')):
      without_include = header.partition('/')[2]
      print('\n' + without_include)
      with open(header) as f:
          line = f.readline()
          if line.startswith('// Copyright'):
              line = f.readline()
              assert line in SEPARATOR_LINES, line
              line = f.readline()
          while line not in SEPARATOR_LINES:
              assert line[2] == ' ', line
              print('    ' + line[3:-1])
              line = f.readline()
  
subject: add script that generates docs/headers.rst