Add docstring and move up the variable at the top of function.

1 files changed, 7 insertions, 1 deletions

diff --git a/pylint/checkers/utils.py b/pylint/checkers/utils.py
index e3f0e2f94..9028c8417 100644
--- a/pylint/checkers/utils.py
+++ b/pylint/checkers/utils.py
@@ -809,6 +809,13 @@ def node_type(node):
 
 
 def is_registered_in_singledispatch_function(node):
+    """Check if the given function node is a singledispatch function."""
+
+    singledispatch_qnames = (
+        'functools.singledispatch',
+        'singledispatch.singledispatch'
+    )
+
     if not isinstance(node, astroid.FunctionDef):
         return False
 
@@ -827,7 +834,6 @@ def is_registered_in_singledispatch_function(node):
         except astroid.InferenceError:
             continue
 
-        singledispatch_qnames = ('functools.singledispatch', 'singledispatch.singledispatch')
         if isinstance(func_def, astroid.FunctionDef):
             return decorated_with(func_def, singledispatch_qnames)