diff --git a/superset/tasks/schedules.py b/superset/tasks/schedules.py
index f4b7911d8..9ae67f5ea 100644
--- a/superset/tasks/schedules.py
+++ b/superset/tasks/schedules.py
@@ -264,7 +264,8 @@ def _get_slice_data(schedule):
         raise URLError(response.getcode())
 
     # TODO: Move to the csv module
-    rows = [r.split(b",") for r in response.content.splitlines()]
+    content = response.read()
+    rows = [r.split(b",") for r in content.splitlines()]
 
     if schedule.delivery_type == EmailDeliveryType.inline:
         data = None
@@ -281,7 +282,7 @@ def _get_slice_data(schedule):
             )
 
     elif schedule.delivery_type == EmailDeliveryType.attachment:
-        data = {__("%(name)s.csv", name=slc.slice_name): response.content}
+        data = {__("%(name)s.csv", name=slc.slice_name): content}
         body = __(
             '<b><a href="%(url)s">Explore in Superset</a></b><p></p>',
             name=slc.slice_name,
diff --git a/tests/schedules_test.py b/tests/schedules_test.py
index da55f9efa..49aa05248 100644
--- a/tests/schedules_test.py
+++ b/tests/schedules_test.py
@@ -378,7 +378,7 @@ class SchedulesTestCase(SupersetTestCase):
         mock_open.return_value = response
         mock_urlopen.return_value = response
         mock_urlopen.return_value.getcode.return_value = 200
-        response.content = self.CSV
+        response.read.return_value = self.CSV
 
         schedule = (
             db.session.query(SliceEmailSchedule)
@@ -404,8 +404,7 @@ class SchedulesTestCase(SupersetTestCase):
         mock_open.return_value = response
         mock_urlopen.return_value = response
         mock_urlopen.return_value.getcode.return_value = 200
-        response.content = self.CSV
-
+        response.read.return_value = self.CSV
         schedule = (
             db.session.query(SliceEmailSchedule)
             .filter_by(id=self.slice_schedule)