In OpenERP, first, create custom module and then configure your incoming and outgoing mail in your server an then relate it to the function.

Follow these step given below:

Step1- First, create module like as a test module and then create file test.py file in your module and pass this file in the __init__.py file.
Using this code show in below

class emailll_systems(osv.osv):    
    _name = emailll.systems
    _columns = {
                'cust_profile' : fields.many2one('customer.profile','Customer Profile'),  
                's
def male_send_doc_verification(self,cr,uid,ids,data,partner,subject,url,user,context=None):
        res_obj = self.pool.get('res.users').browse(cr, uid, uid)
        group = self.pool.get('res.groups').search(cr,uid,[('name', '=', 'Account Manager')])
        users = self.pool.get('res.groups').browse(cr,uid,group)
        if users:
            if users.name=='Account Manager':
                for user in users.users:
                    mail_mail = self.pool.get('mail.mail')
                    this_context = context
                    body = '''
                            Dear ''' " %s," % (data.partner_id.name) + '''
                            <p></p>
                            <p> A Account Type ''' "%s" % data.partner_id.name + '''  for customer ''' "%s" % data.partner_id.name +''' require for verification.</p> 
                            <p></p>
                            <p>Please action it accordingly</p> 
                            <p> </p>
                            <p>You can access account details from  below url </p>
                            <p>''' "%s" % url +''' </p>                             
                            <p>Regards, </p> 
                            '''
                    print "Email to",user.id 
                    mail_values = {
                        'email_from':res_obj.email,
                        'email_to': user.email,
                        'subject': subject,
                        'body_html': body,
                        'state': 'outgoing',
                        'type': 'email',
                        }
                    mail_id = mail_mail.create(cr, uid, mail_values, context=this_context)
                    mail_mail.send(cr, uid, [mail_id],  auto_commit=True, context=this_context)   
        return True    

Step2- After the above step, create another file like as test_workflow.xml file in your own module and pass this file in your __openerp__.py. This file follows the workflow as par your requirement.

Using this code given belowto

<openerp>
    <data>
<!--       workflow -->
        <record id="wkf_emailll.systems" model="workflow">
            <field name="name">emailll.systems.wkf</field>
            <field name="osv">emailll.systems</field>
            <field name="on_create">True</field>
        </record>        
<!--         Activity -->
        <record id="act_draft" model="workflow.activity">
            <field name="wkf_id" ref="wkf_loan_application"/>
            <field name="name">draft</field>
            <field name="flow_start">True</field>
        </record>        
        <record id="act_approval_a" model="workflow.activity">
            <field name="wkf_id" ref="wkf_loan_application"/>
            <field name="name">approval_a</field>
            <field name="kind">function</field>
            <field name="action">action_approval_a()</field>
        </record>       
        <record id="act_approval_b" model="workflow.activity">
            <field name="wkf_id" ref="wkf_loan_application"/>
            <field name="name">approval_b</field>
            <field name="kind">function</field>
            <field name="action">action_approval_b()</field>
        </record>
<!--         Trainsition -->        
        <record id="trans_draft_approval_a" model="workflow.transition">
            <field name="act_from" ref="act_draft"/>
            <field name="act_to" ref="act_approval_a"/>
            <field name="signal">approval_a</field>
        </record>        
        <record id="trans_appr_a_revisn" model="workflow.transition">
            <field name="act_from" ref="act_approval_a"/>
            <field name="act_to" ref="act_revision"/>
            <field name="signal">revision</field>
        </record>      
        <record id="trans_revisn_appr_a" model="workflow.transition">
            <field name="act_from" ref="act_revision"/>
            <field name="act_to" ref="act_approval_a"/>
            <field name="signal">approval_a</field>
        </record>
    </data>
</openerp>