cleanup api data handling

src/util.py

@@ -0,0 +1,17 @@
+def keys_exists(element, *keys):
+    """"
+    Check if *keys (nested) exists in `element` (dict).
+    Thanks stackoverflow: https://stackoverflow.com/questions/43491287/elegant-way-to-check-if-a-nested-key-exists-in-a-dict
+    """
+    if not isinstance(element, dict):
+        raise AttributeError('keys_exists() expects dict as first argument.')
+    if len(keys) == 0:
+        raise AttributeError('keys_exists() expects at least two arguments, one given.')
+
+    _element = element
+    for key in keys:
+        try:
+            _element = _element[key]
+        except KeyError:
+            return False
+    return True