Merge pull request #1377 from graphql-python/fix-graphql-core-dependency

Fix GraphQL-core dependency

Author: syrusakbary

setup.py

@@ -82,7 +82,7 @@ def run_tests(self):
     keywords="api graphql protocol rest relay graphene",
     packages=find_packages(exclude=["examples*"]),
     install_requires=[
-        "graphql-core>=3.1.2,<4",
+        "graphql-core~=3.1.2",
         "graphql-relay>=3.0,<4",
         "aniso8601>=8,<10",
     ],