RVM error rvm:97: parse error near `unset'

$ \curl -sSL https://get.rvm.io | bash -s stable --ruby
Downloading https://github.com/rvm/rvm/archive/1.29.10.tar.gz
Downloading https://github.com/rvm/rvm/releases/download/1.29.10/1.29.10.tar.gz.asc
Found PGP signature at: 'https://github.com/rvm/rvm/releases/download/1.29.10/1.29.10.tar.gz.asc',
but no GPG software exists to validate it, skipping.
Installing RVM to /Users/kant/.rvm/
    RVM PATH line found in /Users/kant/.mkshrc /Users/kant/.profile /Users/kant/.bashrc /Users/kant/.zshrc.
    RVM sourcing line found in /Users/kant/.profile /Users/kant/.bash_profile /Users/kant/.zlogin.
Installation of RVM in /Users/kant/.rvm/ is almost complete:

  * To start using RVM you need to run `source /Users/kant/.rvm/scripts/rvm`
    in all your open shell windows, in rare cases you need to reopen all shell windows.
Thanks for installing RVM 🙏
Please consider donating to our open collective to help us maintain RVM.

👉  Donate: https://opencollective.com/rvm/donate


Ruby enVironment Manager 1.29.10 (latest) (c) 2009-2017 Michal Papis, Piotr Kuczynski, Wayne E. Seguin

Searching for binary rubies, this might take some time.
No binary rubies available for: osx/10.15/x86_64/ruby-2.7.0.
Continuing with compilation. Please read 'rvm help mount' to get more information on binary rubies.
Checking requirements for osx.
Certificates bundle '/usr/local/etc/[email protected]/cert.pem' is already up to date.
Requirements installation successful.
Installing Ruby from source to: /Users/kant/.rvm/rubies/ruby-2.7.0, this may take a while depending on your cpu(s)...
ruby-2.7.0 - #downloading ruby-2.7.0, this may take a while depending on your connection...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 14.0M  100 14.0M    0     0  10.4M      0  0:00:01  0:00:01 --:--:-- 10.4M
ruby-2.7.0 - #extracting ruby-2.7.0 to /Users/kant/.rvm/src/ruby-2.7.0.....
ruby-2.7.0 - #configuring.........................................................................
ruby-2.7.0 - #post-configuration.
ruby-2.7.0 - #compiling........................................................................
ruby-2.7.0 - #installing............
ruby-2.7.0 - #making binaries executable...
Installed rubygems 3.1.2 is newer than 3.0.8 provided with installed ruby, skipping installation, use --force to force installation.
ruby-2.7.0 - #gemset created /Users/kant/.rvm/gems/ruby-2.7.0@global
ruby-2.7.0 - #importing gemset /Users/kant/.rvm/gemsets/global.gems................................................................
ruby-2.7.0 - #generating global wrappers.......
ruby-2.7.0 - #gemset created /Users/kant/.rvm/gems/ruby-2.7.0
ruby-2.7.0 - #importing gemsetfile /Users/kant/.rvm/gemsets/default.gems evaluated to empty gem list
ruby-2.7.0 - #generating default wrappers.......
ruby-2.7.0 - #adjusting #shebangs for (gem irb erb ri rdoc testrb rake).
Install of ruby-2.7.0 - #complete
Ruby was built without documentation, to build it run: rvm docs generate-ri
Creating alias default for ruby-2.7.0....

  * To start using RVM you need to run `source /Users/kant/.rvm/scripts/rvm`
    in all your open shell windows, in rare cases you need to reopen all shell windows.

$ source /Users/kant/.rvm/scripts/rvm
/Users/kant/.rvm/scripts/rvm:97: parse error near `unset'