1. The code will compare if the dates from attendance fit the date_to and date_from of payslip and sum their lates, undertime and overtime.
2.  
3. class awb_hr_payslip_extension(osv.osv):
4.     _name = 'hr.payslip'
5.     _inherit = 'hr.payslip'
6.     
7.     def create(self, cr, uid, vals, context=None):
8.         # get other input model
9.         attendance_model = self.pool.get('hr.attendance')
10.         payslip_model = self.pool.get('hr.payslip')
11.         #payslip = payslip_model.browse(cr, uid, vals['payslip_id'].id, context=context)
12.         
13.         # convert date_to
14.         date_to = vals['date_to'] + " 23:59:59"
15.         # filtering / get records depending on filter: name, date from, date to
16.         # 'name' is datetime field from attendance model
17.         # vals['field name from hr.payslip']
18.         attendance_ids = attendance_model.search(cr, uid, [('employee_id', '=', vals['employee_id']), ('name', '>=', vals['date_from']), ('name', "<=", date_to)], count=False)
19.         
20.         records_list = attendance_model.browse(cr, uid, attendance_ids)
21.         total_late = 0
22.         total_undertime = 0
23.         total_overtime = 0
24.         for record in records_list:
25.             total_late = total_late + record.late
26.             total_undertime = total_undertime + record.undertime
27.             total_overtime = total_overtime + record.overtime
28.         # insert to Other Inputs
29.         other_input_model = self.pool.get('hr.payslip.input')    
30.         other_input_model.create(cr, uid, ['name': 'Total Late'], 'code': 'late_deduction', 'amount': total_late, 'contract_id': vals['contract_id']}, context=None)
31.         other_input.create(cr, uid, {'name': 'Total Undertime', 'code' : 'undertime_deduction', 'amount': total_undertime, 'contract_id': vals['contract_id']}, context=None)
32.         other_input.create(cr, uid, {'name': 'Total Overtime', 'code': 'overtime_pay', 'amount': total_overtime, 'contract_id': vals['contract_id']}, context=None)
33.         
34.         return super(awb_hr_payslip_extension, self).create(cr, uid, vals, context=context)
35. awb_hr_payslip_extension()

this is my error from this code:(

Integrity Error

The operation cannot be completed, probably due to the following:
- deletion: you may be trying to delete a record while other records still reference it
- creation/update: a mandatory field is not correctly set

[object with reference: payslip_id - payslip.id]