Import in example code fail

[pjakobsen]

From bubbles / doc / operations.rst

The following example code fails:

from bubbles import default_context as c
from bubbles import get_object

source = get_object("csv", "data.csv")
duplicates = c.op.duplicates(source)

$python operations.py
Traceback (most recent call last):
File "operations.py", line 2, in
from bubbles import get_object
ImportError: cannot import name get_object