✅ pymongo version: mongodb_backend requires pymongo==3.13.0 and reins…

…talling pymongo cause bson python package error https://stackoverflow.com/questions/12983472/import-pymongo-causes-importerror-cannot-import-name-bson-how-do-you-fix-the

requirements.txt

@@ -1,5 +1,5 @@
 somutils==1.7.2
-pymongo<3.0;python_version<="2.7.18"
+pymongo==3.13.0;python_version<="2.7.18"
 pymongo<4.0;python_version>"2.7.18"
 numpy<1.17;python_version<="2.7.18"
 numpy;python_version>"2.7.18"