How many february's are a perfect rectangle

pretty_februarys.py

from datetime import *
from dateutil.rrule import *
from dateutil.relativedelta import *
 
PRETTY_YEARS = []

def get_pretty_february():
    # look back 100 years
    YEARS_AGO = 100
    TODAY     = date.today()
    YEARSAGO  = TODAY + relativedelta( years = -YEARS_AGO )
    # check which february 1 started on a sunday
    feb_one = list( rrule( MONTHLY, bymonth = ( 2 ), bymonthday = ( 1 ), byweekday = ( SU ), dtstart = YEARSAGO, until = TODAY ) )

    for x in feb_one:
        year = int( x.strftime( '%Y' ) )
        year_check = is_leap_year( year )
    print 'In the past', YEARS_AGO, 'years, there have been', len( PRETTY_YEARS ), 'pretty Februarys'
    print 'The last pretty February was', PRETTY_YEARS[-2]
    print PRETTY_YEARS
	

def is_leap_year( year ):
    """Given a year as an integer (e.g. 2004) it returns True if the year is a leap year,
    and False if it isn't."""
    if year%4 != 0:
        PRETTY_YEARS.append( year )
    elif year%100 !=0:
        return True
    elif year%400 == 0:
        return True
    else:
        PRETTY_YEARS.append( year )

get_pretty_february()

# In the past 100 years, there have been 11 pretty Februarys
# The last pretty February was 2009
# [1925, 1931, 1942, 1953, 1959, 1970, 1981, 1987, 1998, 2009, 2015]