Another small cleanup
diff --git a/cryptography/hazmat/backends/openssl/backend.py b/cryptography/hazmat/backends/openssl/backend.py
index 7746daf..ab3f947 100644
--- a/cryptography/hazmat/backends/openssl/backend.py
+++ b/cryptography/hazmat/backends/openssl/backend.py
@@ -905,7 +905,7 @@
             return False
 
         # We only support ECDSA right now.
-        if isinstance(signature_algorithm, ec.ECDSA) is False:
+        if not isinstance(signature_algorithm, ec.ECDSA):
             return False
 
         # Before 0.9.8m OpenSSL can't cope with digests longer than the curve.