code: def _commonprefix(strings):
      # Similar to os.path.commonprefix
      if not strings:
          return ""
  
      else:
          s1 = min(strings)
          s2 = max(strings)
  
          for i, c in enumerate(s1):
              if c != s2[i]:
                  return s1[:i]
  
          return s1
  
file_path: catboost/contrib/python/prompt-toolkit/py2/prompt_toolkit/completion.py
imports: from __future__ import unicode_literals
  from abc import ABCMeta, abstractmethod
  from six import with_metaclass
label_desc: Use image node_id 2 for calling a global function with example usage: _commonprefix(strings) and returns: str, s1, s1