print("Blah: [",blah_url,blah,"]<br>", file=f)
Output:
Blah: [ http://blah/Pages/Revision.aspx?projectId=541511cd-86bf-46fc-ae70-aec46e6030c7 blah ]<br>
The additional space after the open bracket "[" and before the close bracket "]" shouldn't be there.
It should look like this:
Blah: [http://blah/Pages/Revision.aspx?projectId=541511cd-86bf-46fc-ae70-aec46e6030c7 blah]<br>
I have confirmed there are no extra spaces in the data being supplied as the input.