Fixed a deprecation warning on Python 3.7. Patch by Colin

  Watson. [bug=1847592]

2 files changed, 9 insertions, 1 deletions

diff --git a/CHANGELOG b/CHANGELOG
index 0f14b07..450e8d1 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,11 @@
+= Unreleased
+
+* Fixed a deprecation warning on Python 3.7. Patch by Colin
+  Watson. [bug=1847592]
+
+* Added a Chinese translation by Deron Wang and a Brazilian Portuguese
+  translation by Cezar Peixeiro to the repository.
+
 = 4.8.1 (20191006)
 
 * When the html.parser or html5lib parsers are in use, Beautiful Soup
diff --git a/bs4/element.py b/bs4/element.py
index 2001ad5..8684870 100644
--- a/bs4/element.py
+++ b/bs4/element.py
@@ -163,7 +163,7 @@ class PageElement(object):
             c = XMLFormatter
         else:
             c = HTMLFormatter
-        if callable(formatter):
+        if isinstance(formatter, Callable):
             return c(entity_substitution=formatter)
         return c.REGISTRY[formatter]