In terms of the implementation, it's kind of trivial to implement the "magic", but it would be both confusing and inconsistent, see below.

e.g. imagine a case where you'd want to call datetime.strptime, partially initializing it at the moment of conversion definition. at the moment it is:

  c.call_func(
      datetime.strptime,
      c.item("updated"),
      "%Y-%m-%d"
  )

but it's unclear to me how would the "magic" approach deal with the case above.

Replace your current namespace with a mock object? You can eval or exec code with any dictionary-flavored object, and mocks can imitate dicts.

edit: no, you can't in Python 3..

I'll try to have a closer look later today.