ImportError：无法导入名称opentype

Question

我正在用我得到的这个树莓派建立一个Google Sheets api连接，而python似乎并没有从其所在位置获取pyasn1模块。我尝试删除该文件夹并重新安装了许多其他方法，没有任何工作！请帮忙!!!

  File "./google_spreadsheet.py", line 43, in <module>
    from oauth2client.service_account import ServiceAccountCredentials
  File "/usr/local/lib/python2.7/dist-packages/oauth2client/service_account.py", line 26, in <module>
    from oauth2client import crypt
  File "/usr/local/lib/python2.7/dist-packages/oauth2client/crypt.py", line 23, in <module>
    from oauth2client import _pure_python_crypt
  File "/usr/local/lib/python2.7/dist-packages/oauth2client/_pure_python_crypt.py", line 24, in <module>
    from pyasn1_modules.rfc2459 import Certificate
  File "/usr/local/lib/python2.7/dist-packages/pyasn1_modules/rfc2459.py", line 20, in <module>
    from pyasn1.type import opentype
ImportError: cannot import name opentype