You can use like this here create the date

 'leave_from' : fields.date("Leave Date", required=True), 

 'leave_from' : fields.date("Leave Until", required=True),


def _date_cal(self, cr, uid, ):

     leave_taken = (leave_from-leave_from).days

 i = leave_from
cnt = 0
 while (i <leave_until): if="" (="" i.weekday()="=" 5="" or="" i.weekday()="=" 6):="" cnt="cnt+0" else:="" cnt="cnt+1" i++="" leave_taken="cnt</pre">

Hi pls chk this code.....

maturity_date and deposit_date are two date fields from a same class .By this code u can easily calculate number of days between two dates try this

def calc_maturity_amount(self,cr,uid,ids,context=None):

     num=self.read(cr,uid,ids,['maturity_date','deposit_date','deposit_amount','intr_rate'],context=context)
       dateformat="%Y-%m-%d"
     interst_rate=num[0]['intr_rate']

     d1=datetime.strptime(num[0]['maturity_date'],dateformat)
     d2=datetime.strptime(num[0]['deposit_date'],dateformat)
     v1=d1-d2
     total_days=v1.days