def timestamp_a__d_b_Y_H_M_S_z(value):
a, d, b, Y, t, z = value.split()<EOL>H, M, S = t.split("<STR_LIT::>")<EOL>return int(calendar.timegm((<EOL>int(Y), _months[b.lower()], int(d), int(H), int(M), int(S), <NUM_LIT:0>, <NUM_LIT:0>, <NUM_LIT:0><EOL>))) - _offset(z)<EOL>
Convert timestamp string to time in seconds since epoch.

    Timestamps strings like 'Tue, 18 Jun 2013 22:00:00 +1000' are able to be
    converted by this function.

    Args:
        value: A timestamp string in the format '%a, %d %b %Y %H:%M:%S %z'.

    Returns:
        The time in seconds since epoch as an integer.

    Raises:
        ValueError: If timestamp is invalid.
        KeyError: If the abbrieviated month is invalid.