Yum repository file does not support an underscore after $releasever or $basearch variables

Issue

• When using a name like myrepo_$releasever_$basearch in either name or baseurl entries of a repository file, it does not replace $releasever with the
  version number and $basearch with the architecture :-

# cat /etc/yum.repos.d/myrepo.repo 
[myrepo]
name=myrepo_$releasever_$basearch_Repo
baseurl=file:///mnt
enabled=1
gpgcheck=0


# yum repolist 
Loaded plugins: product-id, refresh-packagekit, search-disabled-repos, security, verify
repo id                  repo name                        status
myrepo             myrepo_$releasever_$basearch_Repo         0