< H2 > ssl error was reported when python2.7.6 on ubuntu installed tornado with pip. < / H2 >

error message

    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-iKNC7g/tornado/setup.py", line 146, in <module>
        raise ImportError("Tornado requires an up-to-date SSL module. This means "
    ImportError: Tornado requires an up-to-date SSL module. This means Python 2.7.9+ or 3.4+ (although some distributions have backported the necessary changes to older versions).
    
    ----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-install-iKNC7g/tornado/

full error

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