old_contents: from django import template
  from datetime import date, datetime, timedelta
  
  register = template.Library()
  
  @register.filter(expects_localtime=True)
  def is_today(value):
      if isinstance(value, datetime):
          value = value.date()
      return value == date.today()
  
  @register.filter(expects_localtime=True)
  def is_past(value):
      if isinstance(value, datetime):
          value = value.date()
      return value < date.today()
  
  @register.filter(expects_localtime=True)
  def is_future(value):
      if isinstance(value, datetime):
          value = value.date()    
      return value > date.today()
  
  @register.filter(expects_localtime=True)
  def compare_today(value):
      if isinstance(value, datetime):
          value = value.date()
      return value - date.today()
  
new_contents: from django import template
  from datetime import date, datetime, timedelta
  
  register = template.Library()
  
  @register.filter(expects_localtime=True)
  def is_today(value):
      if isinstance(value, datetime):
          value = value.date()
      return value == date.today()
  
  @register.filter(expects_localtime=True)
  def is_past(value):
      if isinstance(value, datetime):
          value = value.date()
      return value < date.today()
  
  @register.filter(expects_localtime=True)
  def is_future(value):
      if isinstance(value, datetime):
          value = value.date()    
      return value > date.today()
  
  @register.filter(expects_localtime=True)
  def compare_today(value):
      if isinstance(value, datetime):
          value = value.date()
      return value - date.today()
  
  @register.filter(expects_locattime=True)
  def today_in_season(season):
      start_date = season.season_start_date
      end_date   = season.season_end_date
      return (start_date <= date.today() <= end_date)
          
  
subject: Add new filter to determine if today is within the time period for a season.