a context manager to capture variables

variable_capture.py

import inspect
from contextlib import ContextDecorator

class VariableCapture(ContextDecorator):
    def __enter__(self):
        frame = inspect.currentframe().f_back
        self.keys = {k for k,v in frame.f_locals.items() if k != 'self'}
        return self
    
    def __exit__(self, exc_type, exc_value, traceback):
        if exc_type is None:
            # no exception occurred, capture variables
            frame = inspect.currentframe().f_back
            self.variables = {k:v for k,v in frame.f_locals.items() if k not in self.keys}
        # return False to propagate any exception that occurred
        return False