1 files changed, 4 insertions, 0 deletions
diff --git a/render.py b/render.py
index f7e23f0..3e1d215 100644
--- a/render.py
+++ b/render.py
@@ -9,9 +9,13 @@ class Renderer:
     def __init__(self, output_dir):
         self.env = jinja2.Environment(
             loader = jinja2.FileSystemLoader('./templates'))
+        self.env.filters['select_with_attribute'] = self.select_with_attribute
         self.output_dir = output_dir
         self.templates = {}
 
+    def select_with_attribute(self, iterable, attribute, result=True):
+        return [value for value in iterable if (attribute in value) == result]
+
     def _render(self, template, filename, **kwargs):
         if template not in self.templates:
             self.templates[template] = self.env.get_template(template)