title: Call function in domain Many2one field
body: <p>Is it possible call functin in domain Many2one field?</p>
  
  <p>For example:</p>
  
  <pre><code>time = fields.Many2one('my.time', #call function here)
  </code></pre>
  
  <p>The time field is populated from database table my_time. In table I have several row:</p>
  
  <pre><code>id name
  
  1  10:00
  
  2  11:00
  
  3  12:00
  
  4. 13:00
  </code></pre>
  
  <p>In other table my_booked_time, I insert id (1) from time field, now I need filter Many2one "Select all available time (11:00,12:00,13:00)" not 10:00, where user_id = self.user_id and partner_id = self.partner_id</p>
  
  <p>Any simple solution?</p>