upgrade re_path to path (#533)

core/converters.py

@@ -0,0 +1,35 @@
+from core.models import Page
+
+
+class FourDigitYearConverter:
+    regex = "[0-9]{4}"
+
+    def to_python(self, value):
+        return int(value)
+
+    def to_url(self, value):
+        return str(value).zfill(4)
+
+
+class TwoDigitMonthConverter:
+    regex = "[0-9]{2}"
+
+    def to_python(self, value):
+        return int(value)
+
+    def to_url(self, value):
+        return str(value).zfill(2)
+
+
+class BooleanStringConverter:
+    """
+    Converter whose regex match either True or False
+    """
+
+    regex = r"(True)|(False)"
+
+    def to_python(self, value):
+        return str(value) == "True"
+
+    def to_url(self, value):
+        return str(value)