Is it okay to repeat the period in the file name?

I wonder if it doesn't matter if I repeat the period (.) in the file name. Usually, periods are used to enter file extensions, but sometimes more than two periods are used.

I don't have a problem using it right now, but I want to know if it's a bad habit that needs to be fixed in case it causes a problem later.

There is no problem when using the normal folder path, but in the case of module import, I am a little worried because there are cases where the path is entered with a period.

# File name example
a major classificationFile name.Extension

# When using file path
Route 1 / Route 2 / Route 3 / Large classification. Subclassification.File name.Extension

# When importing(?)
Path 1. Path 2. Path 3. Large classification. Subclassification.File name.Extension