How to use the koji.context.context.handlers.call function in koji

def get_channel_arches(channel):
    """determine arches available in channel"""
    chan = context.handlers.call('getChannel', channel, strict=True)
    ret = {}
    for host in context.handlers.call('listHosts', channelID=chan['id'], enabled=True):
        for a in host['arches'].split():
            ret[koji.canonArch(a)] = 1
    return ret

def get_channel_arches(channel):
    """determine arches available in channel"""
    chan = context.handlers.call('getChannel', channel, strict=True)
    ret = {}
    for host in context.handlers.call('listHosts', channelID=chan['id'], enabled=True):
        for a in host['arches'].split():
            ret[koji.canonArch(a)] = 1
    return ret

def get_channel_arches(channel):
    """determine arches available in channel"""
    chan = context.handlers.call('getChannel', channel, strict=True)
    ret = {}
    for host in context.handlers.call('listHosts', channelID=chan['id'], enabled=True):
        for a in host['arches'].split():
            ret[koji.canonArch(a)] = 1
    return ret

maven_archives.append({'maven_info': maven_info,
                               'files': [os.path.join(dirpath, f) for f in filenames]})

    if not maven_archives:
        return

    # We don't know which pom is the top-level pom, so we don't know what Maven
    # metadata to associate with the build.  So we make something up.
    maven_build = {'group_id': buildinfo['name'], 'artifact_id': rpminfo['name'],
                   'version': '%(version)s-%(release)s' % buildinfo}
    context.handlers.call('host.createMavenBuild', buildinfo, maven_build)

    for entry in maven_archives:
        maven_info = entry['maven_info']
        for filepath in entry['files']:
            if not context.handlers.call('getArchiveType', filename=filepath):
                # unsupported archive type, skip it
                continue
            context.handlers.call('host.importArchive', filepath, buildinfo, 'maven', maven_info)

if len(poms) != 1:
            continue

        pom_info = koji.parse_pom(os.path.join(dirpath, poms[0]))
        maven_info = koji.pom_to_maven_info(pom_info)
        maven_archives.append({'maven_info': maven_info,
                               'files': [os.path.join(dirpath, f) for f in filenames]})

    if not maven_archives:
        return

    # We don't know which pom is the top-level pom, so we don't know what Maven
    # metadata to associate with the build.  So we make something up.
    maven_build = {'group_id': buildinfo['name'], 'artifact_id': rpminfo['name'],
                   'version': '%(version)s-%(release)s' % buildinfo}
    context.handlers.call('host.createMavenBuild', buildinfo, maven_build)

    for entry in maven_archives:
        maven_info = entry['maven_info']
        for filepath in entry['files']:
            if not context.handlers.call('getArchiveType', filename=filepath):
                # unsupported archive type, skip it
                continue
            context.handlers.call('host.importArchive', filepath, buildinfo, 'maven', maven_info)

if not maven_archives:
        return

    # We don't know which pom is the top-level pom, so we don't know what Maven
    # metadata to associate with the build.  So we make something up.
    maven_build = {'group_id': buildinfo['name'], 'artifact_id': rpminfo['name'],
                   'version': '%(version)s-%(release)s' % buildinfo}
    context.handlers.call('host.createMavenBuild', buildinfo, maven_build)

    for entry in maven_archives:
        maven_info = entry['maven_info']
        for filepath in entry['files']:
            if not context.handlers.call('getArchiveType', filename=filepath):
                # unsupported archive type, skip it
                continue
            context.handlers.call('host.importArchive', filepath, buildinfo, 'maven', maven_info)