'Checks if this package is altogether valid on Koji
This verifies if the build or tag specified in the package
specification actually exist on the Koji server
:return: True or False'

def is_pkg_valid(self, pkg):

    valid = True
    if pkg.build:
        if (not self.is_pkg_spec_build_valid(pkg)):
            valid = False
    elif pkg.tag:
        if (not self.is_pkg_spec_tag_valid(pkg)):
            valid = False
    else:
        valid = False
    return valid
