title: OpenERP customized module with button object
body: <p>I have created a customized module i openerp with following .py file . Please help me to add first and second to get third using button object click function.</p>
  
  <pre><code>from osv import osv
  
  from osv import fields
  
  class test_base(osv.osv):
      _name='test.base'
      _columns={
  
  
              'first':fields.integer('First No:'),
              'second':fields.integer('Second No:'),
              'third':fields.integer('Third No:'),    
               }
  
  def get_sum(self, cr, uid, ids,context=None):
  
       #  please add code here to get sum of 'first' and 'second' and assign to variable 'sum'
  
      return {'value':{'third': sum }}
  
  
  
  test_base()
  </code></pre>
  
  <p>xml</p>
  
  <pre><code>&lt;button name="get_sum" string="Click on me to get sum " type="object"/&gt;
  </code></pre>