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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 parse_raw(s, lineno=0):
 """Parse a date from a raw string. The format must be exactly "seconds-since-epoch offset-utc". See the spec for details. """

    timestamp_str, timezone_str = s.split(b' ', 1)
    timestamp = float(timestamp_str)
    try:
        timezone = parse_tz(timezone_str)
    except ValueError:
        raise errors.InvalidTimezone(lineno, timezone_str)
    return timestamp, timezone