'Duplicate Paths' error, but there are no duplicate paths

Hello,

This is the error I continute to get:

File "c:\Users\dusti\python\bams\company_dash\.venv\Lib\site-packages\flask\app.py", line 1821, in full_dispatch_request
rv = self.preprocess_request()
     ^^^^^^^^^^^^^^^^^^^^^^^^^Open an interactive python shell in this frame
File "c:\Users\dusti\python\bams\company_dash\.venv\Lib\site-packages\flask\app.py", line 2312, in preprocess_request
rv = self.ensure_sync(before_func)()
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "c:\Users\dusti\python\bams\company_dash\.venv\Lib\site-packages\dash\dash.py", line 2089, in router
                if callable(title):
                    title = title(**path_variables) if path_variables else title()
 
                return layout, {"title": title}
 
            _validate.check_for_duplicate_pathnames(_pages.PAGE_REGISTRY)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
            _validate.validate_registry(_pages.PAGE_REGISTRY)
 
            # Set validation_layout
            if not self.config.suppress_callback_exceptions:
                self.validation_layout = html.Div(
File "c:\Users\dusti\python\bams\company_dash\.venv\Lib\site-packages\dash\_validate.py", line 444, in check_for_duplicate_pathnames
raise Exception(f"modules {modules} have duplicate paths")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Exception: modules ['src.pages.layouts.login_layout', 'src/pages.layouts.login_layout'] have duplicate paths

However, I am certain that this app doens’t have duplicate paths…
This code is on a feature branch in git, and the branch it comes from runs withouht error.
I also have an assistant helping me with the project - They are running this on their machine without errors… Only I get this error.

The only difference between our setups is that he is on a Mac… But I don’t believe this would make a difference. We are also both running Python 3.11.

I can’t quite understand what is this trying to tell me, in that it is stating the same page twice (once with src. and the other with src/): Exception: modules ['src.pages.layouts.login_layout', 'src/pages.layouts.login_layout'] have duplicate paths

Has anyone else run into anything like this?

ANy help is appreciated!

Hi @anarchocaps

I haven’t seen an error like this before. Could you make a minimal app that reproduces the error?

Another thing that might give some clues is to inspect the dash.page_registry. If you have a large project, there is a handy utility to pretty-print all or parts of dash.page_registry dict. You can find it in the “Tips and Tricks” section here:

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