Packages installed using yum are not getting into /usr/lib64

I am trying to configure matplotlib for python3. Here is where I am stuck now.

matplotlib backend gtk needs pygtk.

raise ImportError("Gtk* backend requires pygtk to be installed.")
ImportError: Gtk* backend requires pygtk to be installed.

It is already installed.

[root@localhost pygtk-2.24.0]# yum install pygtk2.x86_64
Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager
Package pygtk2-2.24.0-9.el7.x86_64 already installed and latest version
Nothing to do

I downloaded the source for pygtk and when I run ./configure, it fails.

checking for PYGOBJECT... no
configure: error: Package requirements (pygobject-2.0 >= 2.21.3) were not met:

No package 'pygobject-2.0' found

[root@localhost pygtk-2.24.0]# yum install pygobject3-devel.x86_64
Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager
Package pygobject3-devel-3.14.0-3.el7.x86_64 already installed and latest version
Nothing to do
[root@localhost pygtk-2.24.0]# yum install pygobject3.x86_64
Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager
Package pygobject3-3.14.0-3.el7.x86_64 already installed and latest version
Nothing to do

I don't see libs for these packages in /usr/lib64. I am not sure if this is the problem.