Return a string representing the timezone offset.
    Remaining seconds are rounded to the nearest minute.

    >>> timezone(3600)
    '+01:00'
    >>> timezone(5400)
    '+01:30'
    >>> timezone(-28800)
    '-08:00'

def timezone(utcoffset):
    '''
    Return a string representing the timezone offset.
    Remaining seconds are rounded to the nearest minute.

    >>> timezone(3600)
    '+01:00'
    >>> timezone(5400)
    '+01:30'
    >>> timezone(-28800)
    '-08:00'

    '''

    hours, seconds = divmod(abs(utcoffset), 3600)
    minutes = round(float(seconds) / 60)

    if utcoffset >= 0:
        sign = '+'
    else:
        sign = '-'
    return '{0}{1:02d}:{2:02d}'.format(sign, int(hours), int(minutes))