Django/Python unittesting: How to Force Exception of Try/Except Block

Is there any way to force the except block to execute so that I can verify the error messages/handling with unit testing? For example:

views.py

def get_books(request):
    ...
    try:
        book = Books.objects.get_or_create(user=request.user)
    except:
        messages.error(request, 'Unable to create new book!')
        return HttpResponseRedirect(reverse('my_books'))

    # more try/except cases

So in this example, how can I simulate basically an ORM failure? Sure, I can try to send in an invalid user for this case, but is there a general way to throw exceptions using libraries? Mock for instance. Or is there some other method to use unittest to force exceptions? Obviously there are going to be many try/except blocks throughout the code, so I'm looking for any help.