main.py

from sentry import report_error

@report_error
def main():
    raise ValueError('test')

sentry.py

import raven


client = Client('https://<key>:<secret>@sentry.io/<project>')


def report_error(fn):
    def wrapper(*args, **kwargs):
        try:
            fn(*args, **kwargs)
        except Exception:
            client.captureException()
            raise
    return wrapper