code: def clone(self, repo_path, destination, branch=None):
          '''Clone a repository to a destination relative to envrionment root'''
  
          logger.debug('Installing ' + repo_path)
          if not destination.startswith(self.env_path):
              destination = unipath(self.env_path, destination)
  
          if branch:
              return shell.run('git', 'clone', repo_path, '--branch', branch,
                               '--single-branch', '--recursive', destination)
  
          return shell.run('git', 'clone', '--recursive', repo_path, destinationf clone(self, repo_path, destination, branch=None):
          '''Clone a repository to a destination relative to envrionment root'''
  
          logger.debug('Installing ' + repo_path)
          if not destination.startswith(self.env_path):
              destination = unipath(self.env_path, destination)
  
          if branch:
              return shell.run('git', 'clone', repo_path, '--branch', branch,
                               '--single-branch', '--recursive', destination)
  
          return shell.run('git', 'clone', '--recursive', repo_path, destination)
docs: Clone a repository to a destination relative to envrionment root