diff --git a/pheme/parameter.py b/pheme/parameter.py
index 3ee9fa9e..820161c3 100644
--- a/pheme/parameter.py
+++ b/pheme/parameter.py
@@ -101,7 +101,7 @@ def __process_form_data(request: HttpRequest, data: Dict) -> Dict:
             "Request data is expected to be a dict, "
             f"but it is {type(request.data)}"
         )
-    for (key, value) in request.data.items():
+    for key, value in request.data.items():
         if isinstance(value, UploadedFile):
             file_type, _ = mimetypes.guess_type(value.name)
             logger.info(
@@ -151,7 +151,6 @@ def __process_single_value(request: HttpRequest, data: Dict) -> Dict:
     ]
 )
 def put(request: HttpRequest) -> Response:
-
     if request.content_type == "application/json":
         return __put(request, __process_json_object)
     return __put(request, __process_form_data)
diff --git a/pheme/templatetags/charts/h_bar.py b/pheme/templatetags/charts/h_bar.py
index 776b7245..c640760f 100644
--- a/pheme/templatetags/charts/h_bar.py
+++ b/pheme/templatetags/charts/h_bar.py
@@ -98,7 +98,6 @@ def h_bar_chart(
     font_family="Dejavu Sans",
     font_size=10,
 ) -> SafeText:
-
     """
     Returns a stacked horizontal bar chart in svg.
 
diff --git a/pheme/templatetags/charts/pie.py b/pheme/templatetags/charts/pie.py
index 378fbe25..d7e4d713 100644
--- a/pheme/templatetags/charts/pie.py
+++ b/pheme/templatetags/charts/pie.py
@@ -99,7 +99,7 @@ def pie_chart(
     dash_array = circumference - border_size
 
     donut = ""
-    for (category, amount) in input_values.items():
+    for category, amount in input_values.items():
         percent = amount / total
         color = title_color.get(category)
         dash_offset = circumference - percent * circumference