there is some really strange problem.

Traceback (most recent call last):
    File "mnist.py", line 17, in 
      import lasagne.nonlinearities as nonlinearities
    File "/usr/local/lib/python2.7/dist-packages/lasagne/init.py", line 17, in 
      from . import nonlinearities
  ImportError: cannot import name nonlinearities

As I go to this folder, I find there is it(the name).but for some unkown reason,(I guess path problem). It does not work.
this may be raised by my mistaking operation, but my mistaking command was not executed.
in detail,originally,my lasagne==0.1.and there is some module can not import..so i solved it by installing the leasted version lasagne==0.2.dev1...then it works.for some reason ,i break my program.before i run it again,i had done some unexecuted mistaking command,now the error is there as you see.i guess it because of two version of lasagne under the path /usr/local/lib/python2.7/dist-packages/..so i uninstall all of them,then i reinstall the one version.but the error is still there..
additional..the following command is ok
    python
    import lasagne
    import lasagne.nonlinearites as nonl
this can be solved by first import lasagne then import theano..
if exchange the import order,then the error arise...
this is very strange.i am not sure what happens,but it does work
from . import nonlinearities cannot import name nonlinearities