Avoid the need to import search_ancestor

jedi/inference/star_args.py

@@ -12,15 +12,12 @@ The signature here for bar should be `bar(b, c)` instead of bar(*args).
 """
 from inspect import Parameter
 
-from parso import tree
-
 from jedi.inference.utils import to_list
 from jedi.inference.names import ParamNameWrapper
 from jedi.inference.helpers import is_big_annoying_library
 
 
 def _iter_nodes_for_param(param_name):
-    from parso.python.tree import search_ancestor
     from jedi.inference.arguments import TreeArguments
 
     execution_context = param_name.parent_context
@@ -28,7 +25,7 @@ def _iter_nodes_for_param(param_name):
     # tree rather than going via the execution context so that we're agnostic of
     # the specific scope we're evaluating within (i.e: module or function,
     # etc.).
-    function_node = tree.search_ancestor(param_name.tree_name, 'funcdef', 'lambdef')
+    function_node = param_name.tree_name.search_ancestor('funcdef', 'lambdef')
     module_node = function_node.get_root_node()
     start = function_node.children[-1].start_pos
     end = function_node.children[-1].end_pos
@@ -38,7 +35,7 @@ def _iter_nodes_for_param(param_name):
             argument = name.parent
             if argument.type == 'argument' \
                     and argument.children[0] == '*' * param_name.star_count:
-                trailer = search_ancestor(argument, 'trailer')
+                trailer = argument.search_ancestor('trailer')
                 if trailer is not None:  # Make sure we're in a function
                     context = execution_context.create_context(trailer)
                     if _goes_to_param_name(param_name, context, name):