Update trial_balance.py

Assuming that Account_number has NUMBERs will sort.
diff --git a/erpnext/accounts/report/trial_balance/trial_balance.py b/erpnext/accounts/report/trial_balance/trial_balance.py
index f484111..7142c69 100644
--- a/erpnext/accounts/report/trial_balance/trial_balance.py
+++ b/erpnext/accounts/report/trial_balance/trial_balance.py
@@ -51,7 +51,7 @@
 		filters.to_date = filters.year_end_date
 
 def get_data(filters):
-	accounts = frappe.db.sql("""select name, parent_account, account_name, root_type, report_type, lft, rgt
+	accounts = frappe.db.sql("""select name, parent_account, account_name, account_number, root_type, report_type, lft, rgt
 		from `tabAccount` where company=%s order by account_name, lft""", filters.company, as_dict=True)
 	company_currency = erpnext.get_company_currency(filters.company)
 
@@ -176,7 +176,7 @@
 def prepare_data(accounts, filters, total_row, parent_children_map, company_currency):
 	data = []
 	tmpaccnt = sorted(accounts)
-	if accounts[0].account_name[0].isnumeric():
+	if not (accounts[0].account_number is None):
 		accounts = tmpaccnt
 	
 	for d in accounts: