fix lint, add test for escape_string

Author: billbsing

convex_api/contract.py

@@ -5,6 +5,8 @@
 
 """
 
+import re
+
 from convex_api.utils import to_address
 
 

tests/intergration/test_contract.py

@@ -48,3 +48,8 @@ def test_convex_api_deploy_contract(convex_url, test_account):
     contract = convex.load_contract(TEST_CONTRACT_NAME)
     assert(contract)
     assert(contract_address == contract.address)
+
+
+def test_convex_api_contract_escape_string():
+    test_text = 'this is a test "string" '
+    assert('this is a test \\"string\\" ' == Contract.escape_string(test_text))