moved affected_package.affected_version_range into the try except block, as this call can fail due the affected_package to be None.

Signed-off-by: Jan-Niclas Struewer <j.n.struewer@gmail.com>

Author: janniclas

vulnerabilities/improvers/default.py

@@ -94,11 +94,11 @@ def get_exact_purls(affected_package: AffectedPackage) -> Tuple[List[PackageURL]
     >>> assert expected == got
     """
 
-    vr = affected_package.affected_version_range
     # We need ``if c`` below because univers returns None as version
     # in case of vers:nginx/*
     # TODO: Revisit after https://github.com/nexB/univers/issues/33
     try:
+        vr = affected_package.affected_version_range
         affected_purls = []
         fixed_versions = []
         if vr: