avoid utils.version dependency in split repos

IPython/html/terminal/__init__.py

@@ -1,7 +1,7 @@
 import os
 
 import terminado
-from IPython.utils.version import check_version
+from ..utils import check_version
 
 if not check_version(terminado.__version__, '0.3.3'):
     raise ImportError("terminado >= 0.3.3 required, found %s" % terminado.__version__)

IPython/html/utils.py

@@ -9,6 +9,7 @@ import errno
 import os
 import stat
 import sys
+from distutils.version import LooseVersion
 
 try:
     from urllib.parse import quote, unquote
@@ -142,6 +143,19 @@ def to_api_path(os_path, root=''):
     return path
 
 
+def check_version(v, check):
+    """check version string v >= check
+
+    If dev/prerelease tags result in TypeError for string-number comparison,
+    it is assumed that the dependency is satisfied.
+    Users on dev branches are responsible for keeping their own packages up to date.
+    """
+    try:
+        return LooseVersion(v) >= LooseVersion(check)
+    except TypeError:
+        return True
+
+
 # Copy of IPython.utils.process.check_pid:
 
 def _check_pid_win32(pid):