fix: relative import with no parent package

backend/src/models.py

@@ -4,7 +4,16 @@ from sqlalchemy import Column, Computed, DateTime, Float, Index, Integer, String
 # https://sqlalchemy-utils.readthedocs.io/en/latest/_modules/sqlalchemy_utils/types/ts_vector.html
 from sqlalchemy.dialects.postgresql import TSVECTOR
 
-from .database import Base
+
+# to correctly work with both alembic and fastapi we have to check
+# if we are run as a module or as a script
+# https://stackoverflow.com/questions/14132789/relative-imports-for-the-billionth-time/14132912
+import sys
+parent_module = sys.modules['.'.join(__name__.split('.')[:-1]) or '__main__']
+if __name__ == '__main__' or parent_module.__name__ == '__main__':
+    from database import Base
+else:
+    from .database import Base
 
 
 class Header(Base):