From 42e459668cb87a153430cb25323b217d30ce6cf5 Mon Sep 17 00:00:00 2001
From: Ian Yon <iyon@entel.cl>
Date: Tue, 5 Nov 2019 19:29:28 -0300
Subject: [PATCH] Support for python 2.7

---
 moto/iam/models.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/moto/iam/models.py b/moto/iam/models.py
index 81c7d09ca..a7035c445 100644
--- a/moto/iam/models.py
+++ b/moto/iam/models.py
@@ -735,7 +735,9 @@ class IAMBackend(BaseBackend):
         )
         if policy.arn in self.managed_policies:
             raise EntityAlreadyExists(
-                f"A policy called {policy_name} already exists. Duplicate names are not allowed."
+                "A policy called {} already exists. Duplicate names are not allowed.".format(
+                    policy_name
+                )
             )
         self.managed_policies[policy.arn] = policy
         return policy