Why do I keep getting this error? "The call daytime(datetime.datetime(2015, 6, 5, 7, 0),daycycle) returns None, not True."

def daytime(time,daycycle): """ Returns true if the time takes place during the day. A time is during the day if it is after sunrise but before sunset, as indicated by the daycycle dicitionary. A daycycle dictionary has keys for several years (as int). The value for each year is also a dictionary, taking strings of the form 'mm-dd'. The value for that key is a THIRD dictionary, with two keys "sunrise" and "sunset". The value for each of those two keys is a string in 24-hour time format. For example, here is what part of a daycycle dictionary might look like: "2015": { "01-01": { "sunrise": "07:35", "sunset": "16:44" }, "01-02": { "sunrise": "07:36", "sunset": "16:45" }, ... } In addition, the daycycle dictionary has a key 'timezone' that expresses the timezone as a string. This function uses that timezone when constructing datetime objects from this set. If the time parameter does not have a timezone, we assume that it is in the same timezone as the daycycle dictionary Parameter time: The time to check Precondition: time is a datetime object Parameter daycycle: The daycycle dictionary Precondition: daycycle is a valid daycycle dictionary, as described above """ # HINT: Use the code from the previous exercise to get sunset AND sunrise # Add a timezone to time if one is missing (the one from the daycycle)

try:

tz_cycle = daycycle['timezone']

except KeyError:

return False

if time.tzinfo is not None:

year1 = time.strftime('%Y')

date1 = time.strftime('%m-%d')

try:

sunrisetime = daycycle[year1][date1]['sunrise']

sunsettime = daycycle[year1][date1]['sunset']

except KeyError:

return False

y = year1 + '-' + date1

y1 = datetime.datetime.strptime(y, '%Y-%m-%d')

y3 = datetime.datetime.strptime(sunrisetime, '%H:%M').time()

y2 = datetime.datetime.combine(y1, y3)

x = y2.isoformat()

y4 = datetime.datetime.strptime(sunsettime, '%H:%M').time()

y5 = datetime.datetime.combine(y1, y4)

x1 = y5.isoformat()

sunrise = str_to_time(x, tz_cycle)

sunset = str_to_time(x1, tz_cycle)

if sunrise < time < sunset:

return True

else:

return False