Directly use monotonic.monotonic (vs optionally using it)

ChangeLog

@@ -2,6 +2,7 @@
   - Allow providing a non-standard (eventlet or
     other condition class) to the r/w lock for
     cases where it is useful to do so.
+  - Directly use monotonic.monotonic.
 0.8:
   - Add fastener logo (from openclipart).
   - Ensure r/w writer -> reader -> writer

fasteners/_utils.py

@@ -17,20 +17,8 @@
 #    under the License.
 
 import logging
-import time
 
-# Use monotonic time in stopwatches if we can get at it...
-#
-# PEP @ https://www.python.org/dev/peps/pep-0418/
-try:
-    now = time.monotonic
-except AttributeError:
-    try:
-        # Try to use the pypi module if it's available (optionally...)
-        from monotonic import monotonic as now
-    except (AttributeError, ImportError):
-        # Ok fallback to the non-monotonic one...
-        now = time.time
+from monotonic import monotonic as now  # noqa
 
 
 LOG = logging.getLogger(__name__)

setup.py

@@ -26,6 +26,7 @@ with open("README.rst", "r") as readme:
 
 install_requires = [
     'six',
+    'monotonic>=0.1',
 ]
 
 setup(