Inline calls to bit_length now that it's trivial (#3966)

* Inline calls to bit_length now that it's trivial

* unused imports

* An comment
diff --git a/tests/test_cryptography_utils.py b/tests/test_cryptography_utils.py
index 290e161..320f7aa 100644
--- a/tests/test_cryptography_utils.py
+++ b/tests/test_cryptography_utils.py
@@ -56,3 +56,8 @@
         assert len(accesses) == 1
         assert t.t == 14
         assert len(accesses) == 1
+
+
+def test_bit_length():
+    assert utils.bit_length(1) == 1
+    assert utils.bit_length(11) == 4