Process dates in librarything import

bookwyrm/importers/librarything_import.py

@@ -1,4 +1,5 @@
 """ handle reading a tsv from librarything """
+import re
 from . import Importer
 
 
@@ -8,3 +9,11 @@ class LibrarythingImporter(Importer):
     service = "LibraryThing"
     delimiter = "\t"
     encoding = "ISO-8859-1"
+
+    def normalize_row(self, entry, mappings):  # pylint: disable=no-self-use
+        """use the dataclass to create the formatted row of data"""
+        normalized = {k: entry.get(v) for k, v in mappings.items()}
+        for date_field in self.date_fields:
+            date = normalized[date_field]
+            normalized[date_field] = re.sub(r"\[|\]", "", date)
+        return normalized