Error:
Odoo Server Error

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/odoo/tools/convert.py", line 745, in parse
    self._tags[rec.tag](rec, de, mode=mode)
  File "/usr/lib/python3/dist-packages/odoo/tools/convert.py", line 666, in _tag_template
    if '.' not in full_tpl_id:
TypeError: argument of type 'NoneType' is not iterable

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 653, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 312, in _handle_exception
    raise pycompat.reraise(type(exception), exception, sys.exc_info()[2])
  File "/usr/lib/python3/dist-packages/odoo/tools/pycompat.py", line 87, in reraise
    raise value
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 695, in dispatch
    result = self._call_function(**self.params)
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 344, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/odoo/service/model.py", line 97, in wrapper
    return f(dbname, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 337, in checked_call
    result = self.endpoint(*a, **kw)
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 939, in __call__
    return self.method(*args, **kw)
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 517, in response_wrap
    response = f(*args, **kw)
  File "/usr/lib/python3/dist-packages/odoo/addons/web/controllers/main.py", line 938, in call_button
    action = self._call_kw(model, method, args, {})
  File "/usr/lib/python3/dist-packages/odoo/addons/web/controllers/main.py", line 926, in _call_kw
    return call_kw(request.env[model], method, args, kwargs)
  File "/usr/lib/python3/dist-packages/odoo/api.py", line 699, in call_kw
    return call_kw_multi(method, model, args, kwargs)
  File "/usr/lib/python3/dist-packages/odoo/api.py", line 690, in call_kw_multi
    result = method(recs, *args, **kwargs)
  File "<decorator-gen-42>", line 2, in button_immediate_install
  File "/usr/lib/python3/dist-packages/odoo/addons/base/module/module.py", line 72, in check_and_log
    return method(self, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/odoo/addons/base/module/module.py", line 450, in button_immediate_install
    return self._button_immediate_function(type(self).button_install)
  File "/usr/lib/python3/dist-packages/odoo/addons/base/module/module.py", line 552, in _button_immediate_function
    modules.registry.Registry.new(self._cr.dbname, update_module=True)
  File "/usr/lib/python3/dist-packages/odoo/modules/registry.py", line 85, in new
    odoo.modules.load_modules(registry._db, force_demo, status, update_module)
  File "/usr/lib/python3/dist-packages/odoo/modules/loading.py", line 380, in load_modules
    loaded_modules, update_module, models_to_check)
  File "/usr/lib/python3/dist-packages/odoo/modules/loading.py", line 274, in load_marked_modules
    perform_checks=perform_checks, models_to_check=models_to_check
  File "/usr/lib/python3/dist-packages/odoo/modules/loading.py", line 181, in load_module_graph
    _load_data(cr, module_name, idref, mode, kind='data')
  File "/usr/lib/python3/dist-packages/odoo/modules/loading.py", line 95, in _load_data
    tools.convert_file(cr, module_name, filename, idref, mode, noupdate, kind, report)
  File "/usr/lib/python3/dist-packages/odoo/tools/convert.py", line 792, in convert_file
    convert_xml_import(cr, module, fp, idref, mode, noupdate, report)
  File "/usr/lib/python3/dist-packages/odoo/tools/convert.py", line 853, in convert_xml_import
    obj.parse(doc.getroot(), mode=mode)
  File "/usr/lib/python3/dist-packages/odoo/tools/convert.py", line 742, in parse
    self.parse(rec, mode)
  File "/usr/lib/python3/dist-packages/odoo/tools/convert.py", line 752, in parse
    exc_info[2]
  File "/usr/lib/python3/dist-packages/odoo/tools/pycompat.py", line 86, in reraise
    raise value.with_traceback(tb)
  File "/usr/lib/python3/dist-packages/odoo/tools/convert.py", line 745, in parse
    self._tags[rec.tag](rec, de, mode=mode)
  File "/usr/lib/python3/dist-packages/odoo/tools/convert.py", line 666, in _tag_template
    if '.' not in full_tpl_id:
odoo.tools.convert.ParseError: "argument of type 'NoneType' is not iterable" while parsing /mnt/extra-addons/pos_session_custom2_extend/views/report2_extend.xml:4, near
<template>
            <t t-extend="report2">
                <t t-jquery="div.page" t-operation="replace">
                    <t t-call="web.basic_layout">
                        <t t-foreach="docs" t-as="o">
                            <div class="page">
                                <style type="text/css">
                                table {
                                    width: 100%;
                                }
                                </style>
                                <div class="text-center">
                                    <t t-set="company" t-value="o.config_id.company_id"/>
                                    <img src="/web/binary/company_logo" style="width: 45%;padding: 2px 8px 0px 13px;float: center;"/>
                                    <br/>
                                    <t t-esc="company.name"/>
                                </div>
                                <center>
                                    <b>REPORTE DE SESIÓN POS</b>
                                    <p>
                                        <!--Date: <br/>-->
                                        <span>CAJERO: </span><span t-field="o.user_id"/><br/>
                                        <b>FECHA DE APERTURA:</b> <span t-field="o.start_at"/><br/>
                                        <b>FECHA DE CIERRE:</b> <span t-field="o.stop_at"/>
                                    </p>
                                    <p>
                                        TOTAL FACTURAS: <span t-esc="o.tickets_num"/><br/>
                                        DESDE: <span t-field="o.ticket_first_id.pos_reference"/><br/>
                                        HASTA: <span t-field="o.ticket_last_id.pos_reference"/>
                                    </p>
                                </center>
                                <hr/>
                                <br/>
                                <center><b>VENTAS CONTADO</b></center>
                                <table>
                                    <t t-set="cash_total" t-value="0"/>
                                    <tbody>
                                        <tr t-foreach="o.statement_ids.filtered(lambda x: x.journal_id.name not in ['Credit', 'CREDITO'])" t-as="i">
                                            <td>
                                                <h4><span t-field="i.journal_id"/></h4>
                                            </td>
                                            <td class="text-right">
                                                <h4><span t-field="i.total_entry_encoding_custom"/></h4>
                                            </td>
                                            <t t-set="cash_total" t-value="cash_total + i.total_entry_encoding_custom"/>
                                        </tr>
                                    </tbody>
                                </table>
                                <br> 
                                </br>
                                <table>
                                    <tbody>
                                        <tr>
                                            <td>Total Ventas Contado (-) Retiros:</td>
                                            <td class="text-right"><span t-esc="cash_total"/></td>
                                        </tr>
                                    </tbody>
                                </table>
                                <t t-call="pos_session_custom2.dline"/>
                                <center><b>VENTAS CREDITO</b></center>
                                <table>
                                    <tbody>
                                        <tr t-foreach="o.statement_ids.filtered(lambda x: x.journal_id.name in ['Credit', 'CREDITO'])" t-as="i">
                                            <td>
                                                <h4><span t-field="i.journal_id"/></h4>
                                            </td>
                                            <td class="text-right">
                                                <h4><span t-field="i.total_entry_encoding_custom"/></h4>
                                            </td>
                                        </tr>
                                    </tbody>
                                </table>
                    
                                <t t-set="summary_by_tax" t-value="o.summary_by_tax()[0]"/>
                                <table>
                                    <tbody>
                                        <tr>
                                            <th><h4><b>TOTAL VENTAS</b></h4></th>
                                            <th class="text-right">
                                <!--   <h4><b><span t-esc="'%.2f' % summary_by_tax.get('tax_bf1')" /></b></h4></th> -->
                                            <h4><b><span t-esc="'%.2f' % .format(summary_by_tax.get('tax_15') + summary_by_tax.get('tax_18') + summary_by_tax.get('tax_bf1') + summary_by_tax.get('tax_bf2') + summary_by_tax.get('tax_bf3'))"/></b></h4></th>
                                        </tr>
                                    </tbody>
                                </table>  			
                                <!-- Bloque de abono a creditos -->

                                <t t-call="pos_session_custom2.dline"/>
                                <center><b>ABONOS A CREDITO</b></center>
                                <table>
                                    <tbody>
                                        <tr t-foreach="o.statement_ids.filtered(lambda x: x.journal_id.name in ['Credit', 'CREDITO'])" t-as="i">
                                            <td>
                                                <h4><span t-field="i.journal_id"/></h4>
                                            </td>
                                            <td class="text-right">
                                                <h4><span t-field="i.total_entry_encoding_custom"/></h4>
                                            </td>
                                        </tr>
                                    </tbody>
                                </table>
                    
                                <t t-set="summary_by_tax" t-value="o.summary_by_tax()[0]"/>
                                <table>
                                    <tbody>
                                        <tr>
                                            <th><h4><b>TOTAL ABONOS DE CREDITOS</b></h4></th>
                                            <th class="text-right">
                                                <h4><b><span t-esc="'%.2f' % summary_by_tax.get('tax_bf1')"/></b></h4></th>                                
                                        </tr>
                                    </tbody>
                                </table>  			

                                <!-- termina el bloque de abono a creditos -->
                                <t t-call="pos_session_custom2.dline"/>
                                <br/>
                                <center><b>CONTROL DE EFECTIVO</b></center>
                                <table>
                                    <tbody>
                                        <tr>
                                            <td>SALDO INICIAL:</td>
                                            <td class="text-right"><span t-field="o.cash_register_balance_start"/></td>
                                        </tr>
                                        <tr>
                                            <td>+ VENTAS</td>
                                            <td class="text-right"><span t-field="o.cash_register_total_entry_encoding_custom"/></td>
                                        </tr>
                                        <tr>
                                            <td>+ DINERO RECIBIDO </td>
                                            <td class="text-right"><span t-field="o.cash_register_total_entry_encoding_put_in"/></td>
                                        </tr>
                                        <tr>
                                            <td>- DINERO RETIRADO </td>
                                            <td class="text-right"><span t-field="o.cash_register_total_entry_encoding_take_out"/></td>
                                        </tr>
                                        <tr>
                                            <td>TOTAL PAYMENT ON CREDIT:</td>
                                            <td class="text-right"><span t-field="o.debit_total"/></td>
                                        </tr>

                                    </tbody>
                                </table>
                                <t t-call="pos_session_custom2.line"/>
                            <table>
                                            
                            </table>
                            <br/>
                                <table>
                                    <tbody>
                                        <tr>
                                            <td>CIERRE SEGÚN LIBROS:</td>
                                            <td class="text-right"><span t-field="o.cash_register_balance_end"/></td>
                                        </tr>
                                    </tbody>
                                </table>
                                <t t-call="pos_session_custom2.line"/>
                                <table>
                                    <tbody>
                                        <tr>
                                            <td>CIERRE REAL:</td>
                                            <td class="text-right"><span t-field="o.cash_register_balance_end_real"/></td>
                                        </tr>
                                    </tbody>
                                </table>
                                <t t-call="pos_session_custom2.dline"/>
                                <table>
                                    <tbody>
                                        <tr>
                                            <td>(-FALTANTE) / SOBRANTE:</td>
                                            <td class="text-right"><span t-field="o.cash_register_difference"/></td>
                                        </tr>
                                    </tbody>
                                </table>
                            </div>
                            <br/>
                            <br/>
                            <br/>
                            <br/>
                            <center><em>FIRMA DEL CAJERO</em></center>
                        </t>
                    </t>
                </t>
            </t>
        </template>