diff --git a/frappe/custom/doctype/custom_field/custom_field.py b/frappe/custom/doctype/custom_field/custom_field.py
index 1466c3309d..a24777a80a 100644
--- a/frappe/custom/doctype/custom_field/custom_field.py
+++ b/frappe/custom/doctype/custom_field/custom_field.py
@@ -47,7 +47,7 @@ class CustomField(Document):
 			frappe.throw(_("Fieldname not set for Custom Field"))
 
 		if self.fieldname in fieldnames:
-			frappe.throw(_("A field with the name '{}' already exists in doctype {}.".format(self.fieldname, self.dt)))
+			frappe.throw(_("A field with the name '{}' already exists in doctype {}.").format(self.fieldname, self.dt))
 
 		if self.get('translatable', 0) and not supports_translation(self.fieldtype):
 			self.translatable = 0