class_docstr: path implementation that offers access to (possibly remote) subversion
  repositories. 
docstr: execute an svn command, append our own url and revision 
code: def _svnwithrev(self, cmd, *args):
      """execute an svn command, append our own url and revision"""
      if self.rev is None:
          return self._svnwrite(cmd, *args)
      else:
          args = ["-r", self.rev] + list(args)
          return self._svnwrite(cmd, *args)
  
imports: import os, sys, time, re
  import py
  from py import path, process
  from py._path import common
  from py._path import svnwc
  from py._path.cacheutil import BuildcostAccessCache, AgingCache
label_desc: Use image node_id 3 for calling the SvnCommandPath obj's underlying member method code with example usage: obj._svnwithrev(cmd) and returns: self, self