code: def get_prefix_envname(self, name, log=False):
          
          prefix = None
          if name == 'root':
              prefix = self.ROOT_PREFIX
  
  #        envs, error = self.get_envs().communicate()
          envs = self.get_envs()
          for p in envs:
              if basename(p) == name:
                  prefix = p
  
          return prefix
docs: Return full prefix path of environment defined by `name`.