In OpenERP first create custom module and inherit the email_template object in your own module. Then create templates in .xml file.

Follow these step given below:

Step1- First, create module like: test and then create .py file like as: test.py file in your module and pass this file in __init__.py file.

Using this code given below
class email_template_send_wizard(osv.osv_memory):
    _name = 'email_template.send.wizard'                                    
    _inherit = 'email_template.send.wizard'
    def save_to_mailbox(self, cr, uid, ids, context=None):
        user = self.pool.get('res.users').browse(cr, uid, uid).name
        def get_end_value(id, value):
            if len(context['src_rec_ids']) > 1: # Multiple Mail: Gets value from the template
                return self.get_value(cr, uid, template, value, context, id)
            else:
                return value  
        if context is None:
            context = {}
        mail_ids = []
        template = self._get_template(cr, uid, context)
        for id in context['src_rec_ids']:
            screen_vals = self.read(cr, uid, ids[0], [],context)
            
            account = self.pool.get('email_template.account').read(cr, uid, screen_vals['from'], context=context)
            vals = {
                'email_from': tools.ustr(account['name']) + "<" + tools.ustr(account['email_id']) + ">",
                'email_to': get_end_value(id, screen_vals['to']),
                'email_cc': get_end_value(id, screen_vals['cc']),
                'email_bcc': get_end_value(id, screen_vals['bcc']),
                'subject': get_end_value(id, screen_vals['subject']),
                'body_text': get_end_value(id, screen_vals['body_text']),
                'body_html': get_end_value(id, screen_vals['body_html']),
                'account_id': screen_vals['from'],
                'state':'na',
                'mail_type':'multipart/alternative',
            }
            body = vals['body_text']
            vals['body_text'] = (body or ' ') + '\n\nFrom:\n' + str(user)
            
            if screen_vals['signature']:
                signature = self.pool.get('res.users').read(cr, uid, uid, ['signature'], context)['signature']
                if signature:
                    vals['body_text'] = tools.ustr(vals['body_text'] or '') + signature
                    vals['body_html'] = tools.ustr(vals['body_html'] or '') + signature
  
            attachment_ids = []
            #Create partly the mail and later update attachments
            mail_id = self.pool.get('email_template.mailbox').create(cr, uid, vals, context)
            mail_ids.append(mail_id)
            if template.report_template:
                reportname = 'report.' + self.pool.get('ir.actions.report.xml').read(cr, uid, template.report_template.id, ['report_name'], context)['report_name']
                data = {}
                data['model'] = self.pool.get('ir.model').browse(cr, uid, screen_vals['rel_model'], context).model
    
                ctx = context.copy()
                if template.lang:
                    ctx['lang'] = self.get_value(cr, uid, template, template.lang, context, id)
                service = netsvc.LocalService(reportname)
                (result, format) = service.create(cr, uid, [id], data, ctx)
                attachment_id = self.pool.get('ir.attachment').create(cr, uid, {
                    'name': _('%s (Email Attachment)') % tools.ustr(vals['subject']),
                    'datas': base64.b64encode(result),
                    'datas_fname': tools.ustr(get_end_value(id, screen_vals['report']) or _('Report')) + "." + format,
                    'description': vals['body_text'] or _("No Description"),
                    'res_model': 'email_template.mailbox',
                    'res_id': mail_id
                }, context)
                attachment_ids.append( attachment_id )   
            # Add document attachments
            for attachment_id in screen_vals.get('attachment_ids',[]):
                new_id = self.pool.get('ir.attachment').copy(cr, uid, attachment_id, {
                    'res_model': 'email_template.mailbox',
                    'res_id': mail_id,
                }, context)
                attachment_ids.append( new_id )   
            if attachment_ids:
                self.pool.get('email_template.mailbox').write(cr, uid, mail_id, {
                    'attachments_ids': [[6, 0, attachment_ids]],
                    'mail_type': 'multipart/mixed'
                }, context)
        return mail_ids
email_template_send_wizard()

Step2- Then, create another file like: a test.xml file in your own module and pass this file in the __openerp__.py file.

Use this code given below

<?xml version="1.0" encoding="UTF-8"?>
<openerp>
    <data>
  
 		<record model="ir.ui.view" id="email_template_send_wizard_form_ezure_1">
				<field name="name">email_template.send.wizard.form</field>
				<field name="model">email_template.send.wizard</field>
				<field name="inherit_id" ref="email_template.email_template_send_wizard_form"/>
				<field name="type">form</field>
				<field name="arch" type="xml">
				<field name="bcc" select="2" colspan="4" position="replace">
				<field name="bcc" select="2" colspan="4" invisible="1"/>
					</field>
				</field>
               </record>
    </data>
</openerp>