okay, I tried to run this locally (not in Colab):
from transformers import pipeline

translator = pipeline("translation", model="Helsinki-NLP/opus-mt-en-de")

translation = translator("hello, my name is Bob")

print(translation)

and it printed out:
[{'translation_text': 'Hallo, mein Name ist Bob.'}]

I don’t know where you try run that code, but seems to work ok for me. Have you installed latest package of transformers?
pip install transformers -U
Where do you run that code?
Can you share the full code to see if something else is going on there?