refactor(treewide): formatting and ruff fixes, + manually enabled F401

Signed-off-by: Akhil Narang <me@akhilnarang.dev>
diff --git a/erpnext/controllers/item_variant.py b/erpnext/controllers/item_variant.py
index 1eee9ea..7a1db6d 100644
--- a/erpnext/controllers/item_variant.py
+++ b/erpnext/controllers/item_variant.py
@@ -64,9 +64,7 @@
 	variant.flags.ignore_mandatory = True
 	variant.save()
 
-	if not frappe.db.exists(
-		"Item Manufacturer", {"item_code": variant.name, "manufacturer": manufacturer}
-	):
+	if not frappe.db.exists("Item Manufacturer", {"item_code": variant.name, "manufacturer": manufacturer}):
 		manufacturer_doc = frappe.new_doc("Item Manufacturer")
 		manufacturer_doc.update(
 			{
@@ -130,9 +128,7 @@
 		)
 
 
-def validate_item_attribute_value(
-	attributes_list, attribute, attribute_value, item, from_variant=True
-):
+def validate_item_attribute_value(attributes_list, attribute, attribute_value, item, from_variant=True):
 	allow_rename_attribute_value = frappe.db.get_single_value(
 		"Item Variant Settings", "allow_rename_attribute_value"
 	)
@@ -179,9 +175,7 @@
 
 
 def find_variant(template, args, variant_item_code=None):
-	possible_variants = [
-		i for i in get_item_codes_by_attributes(args, template) if i != variant_item_code
-	]
+	possible_variants = [i for i in get_item_codes_by_attributes(args, template) if i != variant_item_code]
 
 	for variant in possible_variants:
 		variant = frappe.get_doc("Item", variant)
@@ -357,7 +351,9 @@
 			if variant.attributes:
 				attributes_description = item.description + " "
 				for d in variant.attributes:
-					attributes_description += "<div>" + d.attribute + ": " + cstr(d.attribute_value) + "</div>"
+					attributes_description += (
+						"<div>" + d.attribute + ": " + cstr(d.attribute_value) + "</div>"
+					)
 
 				if attributes_description not in variant.description:
 					variant.description = attributes_description
@@ -391,8 +387,8 @@
 		abbreviations.append(abbr_or_value)
 
 	if abbreviations:
-		variant.item_code = "{0}-{1}".format(template_item_code, "-".join(abbreviations))
-		variant.item_name = "{0}-{1}".format(template_item_name, "-".join(abbreviations))
+		variant.item_code = "{}-{}".format(template_item_code, "-".join(abbreviations))
+		variant.item_name = "{}-{}".format(template_item_name, "-".join(abbreviations))
 
 
 @frappe.whitelist()