Delta Packages failes - 08/11/2015

Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
warning: /tmp/yum/x86_64/7/openstack-liberty/packages/python-requests-2.7.0-6.el7.noarch.rpm: Header V4 RSA/SHA1 Signature, key ID 764429e6: NOKEY
Public key for python-requests-2.7.0-6.el7.noarch.rpm is not installed
warning: /tmp/yum/x86_64/7/epel/packages/python-boto-2.38.0-2.el7.noarch.rpm: Header V3 RSA/SHA256 Signature, key ID 352c64e5: NOKEY
Public key for python-boto-2.38.0-2.el7.noarch.rpm is not installed
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Total                                               41 MB/s |  61 MB  00:01
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-SIG-Cloud
Importing GPG key 0x764429E6:
 Userid     : "CentOS Cloud SIG (http://wiki.centos.org/SpecialInterestGroup/Cloud) <security@centos.org>"
 Fingerprint: 736a f511 6d9c 40e2 af6b 074b f9b9 fee7 7644 29e6
 Package    : rdo-release-liberty-2.noarch (@/rdo-release-liberty)
 From       : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-SIG-Cloud
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7
Importing GPG key 0x352C64E5: