Cannot detect whether a sequence from the oeis is dead without warning

[mantepse]

Steps To Reproduce

In a fresh session,

sage: s = oeis(17)
sage: s.is_dead()
/home/martin/sage/src/sage/databases/oeis.py:1153: RuntimeWarning: This sequence is dead: "A000017: Erroneous version of A032522."
  warn('This sequence is dead: "{}: {}"'.format(self.id(), self.name()), RuntimeWarning)
True

Expected Behavior

It should just return the result, without triggering the warning.

Actual Behavior

A warning is triggered, which is annoying when processing many sequences.

Additional Information

The reason is that OEISSequence._field issues a warning when the sequence is dead, and this cannot be bypassed.

I see two possible solutions:

• have a keyword warn for _field(self, warn=True) and, in is_dead, do "dead" in self._field('K', warn=False)[0].
• check the raw_entry in is_dead directly, e.g., ["dead" in l[11:] for l in s.raw_entry().splitlines() if l[1] == "K"]

Environment

irrelevant.

Checklist

• I have searched the existing issues for a bug report that matches the one I want to file, without success.
• I have read the documentation and troubleshoot guide