How do I import a range of commits I git fast-expo

Question

I exported a range of commits (a branch) via git fast-export using:

$ git fast-export master...zzz-utumno-refactoring_master > my_original_utumno_r\
efactoring_master_branch_before_rebases

Now I am trying to reimport it. The closest I got was:

$ cat my_original_utumno_refactoring_master_branch_before_rebases | git fast-im\
port
fatal: Branch name doesn't conform to GIT standards: master...zzz-utumno-refacto
ring_master
fast-import: dumping crash report to .git/fast_import_crash_4268

Edit: had also tried:

$ git fast-import < my_original_utumno_refactoring_master_branch_before_rebases
fatal: Branch name doesn't conform to GIT standards: master...zzz-utumno-refacto
ring_master
fast-import: dumping crash report to .git/fast_import_crash_4720

git-fast-import does not give me any clues. How should I proceed ?

Some links I did not quite grok:

• Malformed branch name in fast-export when specifying non-HEAD/branch revision
• Import changes into a git repository from universal diff
• Using git fast-export to export a repo starting at a given commit