diff --git a/tests/test_form_xml.py b/tests/test_form_xml.py
index 74f8d9f..16e69b4 100644
--- a/tests/test_form_xml.py
+++ b/tests/test_form_xml.py
@@ -6,13 +6,13 @@
 """Tests for `facho` package."""
 
 import pytest
-from datetime import datetime
+# from datetime import datetime
 import copy
 
 from facho.fe import form
 from facho.fe import form_xml
+# from fixtures import *
 
-from fixtures import *
 
 def test_import_DIANInvoiceXML():
     try:
@@ -27,70 +27,80 @@ def test_import_DIANDebitNoteXML():
     except AttributeError:
         pytest.fail("unexpected not found")
 
+
 def test_import_DIANCreditNoteXML():
     try:
         form_xml.DIANCreditNoteXML
     except AttributeError:
         pytest.fail("unexpected not found")
 
+
 def test_allowance_charge_in_invoice(simple_invoice_without_lines):
     inv = copy.copy(simple_invoice_without_lines)
     inv.add_invoice_line(form.InvoiceLine(
-        quantity = form.Quantity(1, '94'),
-        description = 'producto facho',
-        item = form.StandardItem(9999),
-        price = form.Price(
-            amount = form.Amount(100.0),
-            type_code = '01',
-            type = 'x'
+        quantity=form.Quantity(1, '94'),
+        description='productofacho',
+        item=form.StandardItem(9999),
+        price=form.Price(
+            amount=form.Amount(100.0),
+            type_code='01',
+            type='x'
         ),
-        tax = form.TaxTotal(
-            subtotals = [
+        tax=form.TaxTotal(
+            subtotals=[
                 form.TaxSubTotal(
-                    percent = 19.0,
-                )
-            ]
+                    percent=19.0,
+                )]
         )
     ))
+
     inv.add_allowance_charge(form.AllowanceCharge(amount=form.Amount(19.0)))
     inv.calculate()
-    
+
     xml = form_xml.DIANInvoiceXML(inv)
     assert xml.get_element_text('./cac:AllowanceCharge/cbc:ID') == '1'
-    assert xml.get_element_text('./cac:AllowanceCharge/cbc:ChargeIndicator') == 'true'
-    assert xml.get_element_text('./cac:AllowanceCharge/cbc:Amount') == '19.0'
-    assert xml.get_element_text('./cac:AllowanceCharge/cbc:BaseAmount') == '100.0'
+    assert xml.get_element_text(
+        './cac:AllowanceCharge/cbc:ChargeIndicator') == 'true'
+    assert xml.get_element_text(
+        './cac:AllowanceCharge/cbc:Amount') == '19.0'
+    assert xml.get_element_text(
+        './cac:AllowanceCharge/cbc:BaseAmount') == '100.0'
+
 
 def test_allowance_charge_in_invoice_line(simple_invoice_without_lines):
     inv = copy.copy(simple_invoice_without_lines)
     inv.add_invoice_line(form.InvoiceLine(
-        quantity = form.Quantity(1, '94'),
-        description = 'producto facho',
-        item = form.StandardItem(9999),
-        price = form.Price(
-            amount = form.Amount(100.0),
-            type_code = '01',
-            type = 'x'
+        quantity=form.Quantity(1, '94'),
+        description='producto facho',
+        item=form.StandardItem(9999),
+        price=form.Price(
+            amount=form.Amount(100.0),
+            type_code='01',
+            type='x'
         ),
-        tax = form.TaxTotal(
-            subtotals = [
+        tax=form.TaxTotal(
+            subtotals=[
                 form.TaxSubTotal(
-                    percent = 19.0,
-                )
-            ]
+                    percent=19.0,
+                )]
         ),
-        allowance_charge = [
+        allowance_charge=[
             form.AllowanceChargeAsDiscount(amount=form.Amount(10.0))
         ]
     ))
     inv.calculate()
 
     # se aplico descuento
-    assert inv.invoice_legal_monetary_total.line_extension_amount == form.Amount(90.0)
-    
+    assert inv.invoice_legal_monetary_total.line_extension_amount == (
+        form.Amount(90.0))
+
     xml = form_xml.DIANInvoiceXML(inv)
 
     with pytest.raises(AttributeError):
-        assert xml.get_element_text('/fe:Invoice/cac:AllowanceCharge/cbc:ID') == '1'
-    xml.get_element_text('/fe:Invoice/cac:InvoiceLine/cac:AllowanceCharge/cbc:ID') == '1'
-    xml.get_element_text('/fe:Invoice/cac:InvoiceLine/cac:AllowanceCharge/cbc:BaseAmount') == '100.0'
+        assert xml.get_element_text(
+            '/fe:Invoice/cac:AllowanceCharge/cbc:ID') == '1'
+    xml.get_element_text(
+        '/fe:Invoice/cac:InvoiceLine/cac:AllowanceCharge/cbc:ID') == '1'
+    xml.get_element_text(
+        '/fe:Invoice/cac:InvoiceLine/cac:AllowanceCharge/cbc:BaseAmount'
+    ) == '100.0'