refactor: convert class method to standalone function

(cherry picked from commit 1ea1bfebc4)

erpnext/accounts/utils.py

@@ -1845,3 +1845,74 @@ class QueryPaymentLedger(object):
 		self.query_for_outstanding()
 
 		return self.voucher_outstandings
+
+
+def create_gain_loss_journal(
+	company,
+	party_type,
+	party,
+	party_account,
+	gain_loss_account,
+	exc_gain_loss,
+	dr_or_cr,
+	reverse_dr_or_cr,
+	ref1_dt,
+	ref1_dn,
+	ref1_detail_no,
+	ref2_dt,
+	ref2_dn,
+	ref2_detail_no,
+) -> str:
+	journal_entry = frappe.new_doc("Journal Entry")
+	journal_entry.voucher_type = "Exchange Gain Or Loss"
+	journal_entry.company = company
+	journal_entry.posting_date = nowdate()
+	journal_entry.multi_currency = 1
+
+	party_account_currency = frappe.get_cached_value("Account", party_account, "account_currency")
+
+	if not gain_loss_account:
+		frappe.throw(_("Please set default Exchange Gain/Loss Account in Company {}").format(company))
+	gain_loss_account_currency = get_account_currency(gain_loss_account)
+	company_currency = frappe.get_cached_value("Company", company, "default_currency")
+
+	if gain_loss_account_currency != company_currency:
+		frappe.throw(_("Currency for {0} must be {1}").format(gain_loss_account, company_currency))
+
+	journal_account = frappe._dict(
+		{
+			"account": party_account,
+			"party_type": party_type,
+			"party": party,
+			"account_currency": party_account_currency,
+			"exchange_rate": 0,
+			"cost_center": erpnext.get_default_cost_center(company),
+			"reference_type": ref1_dt,
+			"reference_name": ref1_dn,
+			"reference_detail_no": ref1_detail_no,
+			dr_or_cr: abs(exc_gain_loss),
+			dr_or_cr + "_in_account_currency": 0,
+		}
+	)
+
+	journal_entry.append("accounts", journal_account)
+
+	journal_account = frappe._dict(
+		{
+			"account": gain_loss_account,
+			"account_currency": gain_loss_account_currency,
+			"exchange_rate": 1,
+			"cost_center": erpnext.get_default_cost_center(company),
+			"reference_type": ref2_dt,
+			"reference_name": ref2_dn,
+			"reference_detail_no": ref2_detail_no,
+			reverse_dr_or_cr + "_in_account_currency": 0,
+			reverse_dr_or_cr: abs(exc_gain_loss),
+		}
+	)
+
+	journal_entry.append("accounts", journal_account)
+
+	journal_entry.save()
+	journal_entry.submit()
+	return journal_entry.name