'execute an svn command, append our own url'

def _svnwrite(self, cmd, *args):

    l = [('svn    %s' % cmd)]
    args = [('"%s"' % self._escape(item)) for item in args]
    l.extend(args)
    l.append(('"%s"' % self._encodedurl()))
    string = '    '.join(l)
    if DEBUG:
        print ('execing    %s' % string)
    out = self._svncmdexecauth(string)
    return out
