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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def public_dsn(dsn):
    '''Transform a standard Sentry DSN into a public one'''
    m = RE_DSN.match(dsn)
    if not m:
        log.error('Unable to parse Sentry DSN')
    public = '{scheme}://{client_id}@{domain}/{site_id}'.format(
        **m.groupdict())
    return public