diff --git a/jedi/parser/python/tree.py b/jedi/parser/python/tree.py
index 43b5e977..5310dbfd 100644
--- a/jedi/parser/python/tree.py
+++ b/jedi/parser/python/tree.py
@@ -512,10 +512,6 @@ class Function(ClassOrFunc):
         except IndexError:
             return None
 
-    def _get_paramlist_code(self):
-        return self.children[2].get_code()
-
-
 class Lambda(Function):
     """
     Lambdas are basically trimmed functions, so give it the same interface.
@@ -543,9 +539,6 @@ class Lambda(Function):
         """
         raise AttributeError("lambda is not named.")
 
-    def _get_paramlist_code(self):
-        return '(' + ''.join(param.get_code() for param in self.params).strip() + ')'
-
     def _get_param_nodes(self):
         return self.children[1:-2]
 
@@ -554,7 +547,6 @@ class Lambda(Function):
         """
         Returns `None`, lambdas don't have annotations.
         """
-        # lambda functions do not support annotations
         return None
 
     def __repr__(self):
diff --git a/jedi/parser_utils.py b/jedi/parser_utils.py
index df340f6b..a3d97be9 100644
--- a/jedi/parser_utils.py
+++ b/jedi/parser_utils.py
@@ -154,7 +154,12 @@ def get_call_signature(funcdef, width=72, call_string=None):
             call_string = '<lambda>'
         else:
             call_string = funcdef.name.value
-    code = call_string + funcdef._get_paramlist_code()
+    if funcdef.type == 'lambdef':
+        p = '(' + ''.join(param.get_code() for param in funcdef.params).strip() + ')'
+    else:
+        p = funcdef.children[2].get_code()
+    code = call_string + p
+
     return '\n'.join(textwrap.wrap(code, width))