text: # call with: source ./thisfile.py
  # if interactive, uncomment:
  #uncomment: python
  import re
  txt=gdb.execute('info args', to_string=True)
  regex = r'\s+clist = std::vector of length (\d+),'
  res = re.findall(regex, txt)
  gdb.execute('set $clist_len = %s' % res[0])
  #uncomment: end
  