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A while ago I asked this question Memoizing decorator that can retry and then promptly forgot about it. I more recently saw Python decorator for retrying w/exponential backoff and wanted to add backoff, but figured I should improve what I already have first. I have taken some of the suggestions of the original, but really I've just completely reimagined it (and if I do say so myself, rather cleverly too). My biggest issue with this is that I'm not sure that my current distinction between "exceptions that get suppressed but not remembered" and "exceptions that get remembered" seems like it might be a bit confusing - is there a friendlier interface here?

import functools
from types import MappingProxyType as FrozenDict
class Memoizer:
 def __init__(self, retry_times=0, suppressed_exceptions=tuple(), capture_exceptions=False):
 self.retry = retry
 self.retry_times = retry_times
 self.suppressed_exceptions = suppressed_exceptions
 self.capture_exceptions = capture_exceptions
 def __call__(self, function):
 d = {}
 @functools.wraps(function)
 def wrapper(*args, **kwargs, __forget=False):
 key = (args, FrozenDict(kwargs))
 if key not in d or __forget:
 i = self.retry_times
 while i > 1:
 try:
 d[key] = function(*args, **kwargs)
 except self.suppressed_exceptions:
 continue
 except Exception as e:
 if self.capture_exceptions:
 d[key] = e
 break
 raise
 else:
 break
 i -= 1
 else:
 # If we didn't already break out, the last attempt shouldn't suppress exceptions
 d[key] = function(*args, **kwargs)
 return d[key]
 return wrapper