How to use the conda.models.channel.Channel function in conda

def test_channel_alias_channels(self):
        channel = Channel('binstar/label/dev')
        assert channel.channel_name == "binstar/label/dev"
        assert channel.channel_location == "conda.anaconda.org"
        assert channel.platform is None
        assert channel.package_filename is None
        assert channel.canonical_name == "binstar/label/dev"
        assert channel.urls() == [
            'https://conda.anaconda.org/binstar/label/dev/%s' % context.subdir,
            'https://conda.anaconda.org/binstar/label/dev/noarch',
        ]

        channel = Channel('binstar/label/dev/win-32')
        assert channel.channel_name == "binstar/label/dev"
        assert channel.channel_location == "conda.anaconda.org"
        assert channel.platform == 'win-32'
        assert channel.package_filename is None
        assert channel.canonical_name == "binstar/label/dev"
        assert channel.urls() == [
            'https://conda.anaconda.org/binstar/label/dev/win-32',
            'https://conda.anaconda.org/binstar/label/dev/noarch',
        ]

def test_bare_channel_file(self):
        url = "file:///conda-01"
        channel = Channel(url)
        assert channel.scheme == "file"
        assert channel.location == "/"
        assert channel.platform is None
        assert channel.canonical_name == url
        assert channel.name == "conda-01"

        assert channel.base_url == url
        assert channel.url() == join_url(url, context.subdir)
        assert channel.urls() == [
            join_url(url, context.subdir),
            join_url(url, 'noarch'),
        ]

def test_basic_get_reduced_index(self):
        get_reduced_index(None, (Channel('defaults'), Channel('conda-test')), context.subdirs,
                          (MatchSpec('flask'), ), 'repodata.json')

def test_pkgs_pro(self):
        channel = Channel('pkgs/pro')
        assert channel.channel_name == "pkgs/pro"
        assert channel.channel_location == "192.168.0.15:8080"
        assert channel.canonical_name == "defaults"
        assert channel.urls() == [
            'http://192.168.0.15:8080/pkgs/pro/%s' % self.platform,
            'http://192.168.0.15:8080/pkgs/pro/noarch',
        ]

        channel = Channel('https://repo.anaconda.com/pkgs/pro')
        assert channel.channel_name == "pkgs/pro"
        assert channel.channel_location == "repo.anaconda.com"
        assert channel.canonical_name == "defaults"
        assert channel.urls() == [
            'https://repo.anaconda.com/pkgs/pro/%s' % self.platform,
            'https://repo.anaconda.com/pkgs/pro/noarch',
        ]

def test_canonicalized_url_gets_correct_token(self):
        channel = Channel("bioconda")
        assert channel.urls() == [
            "https://10.2.3.4:8080/conda/bioconda/%s" % self.platform,
            "https://10.2.3.4:8080/conda/bioconda/noarch",
        ]
        assert channel.urls(with_credentials=True) == [
            "https://10.2.3.4:8080/conda/t/tk-123-45/bioconda/%s" % self.platform,
            "https://10.2.3.4:8080/conda/t/tk-123-45/bioconda/noarch",
        ]

        channel = Channel("https://10.2.3.4:8080/conda/bioconda")
        assert channel.urls() == [
            "https://10.2.3.4:8080/conda/bioconda/%s" % self.platform,
            "https://10.2.3.4:8080/conda/bioconda/noarch",
        ]
        assert channel.urls(with_credentials=True) == [
            "https://10.2.3.4:8080/conda/t/tk-123-45/bioconda/%s" % self.platform,

def get_solver_aggregate_1(specs_to_add=(), specs_to_remove=(), prefix_records=(), history_specs=()):
    PrefixData._cache_.clear()
    pd = PrefixData(TEST_PREFIX)
    pd._PrefixData__prefix_records = {rec.name: PrefixRecord.from_objects(rec) for rec in prefix_records}
    spec_map = {spec.name: spec for spec in history_specs}
    get_index_r_2(context.subdir)
    get_index_r_4(context.subdir)
    with patch.object(History, 'get_requested_specs_map', return_value=spec_map):
        solver = Solver(TEST_PREFIX, (Channel('channel-2'), Channel('channel-4'), ),
                        (context.subdir,), specs_to_add=specs_to_add, specs_to_remove=specs_to_remove)
        yield solver

def channel_str(rec):
        if rec.get('schannel'):
            return rec['schannel']
        if rec.get('url'):
            return Channel(rec['url']).canonical_name
        if rec.get('channel'):
            return Channel(rec['channel']).canonical_name
        return UNKNOWN_CHANNEL

def __init__(self, channel, repodata_fn=REPODATA_FN):
        assert channel.subdir
        if channel.package_filename:
            parts = channel.dump()
            del parts['package_filename']
            channel = Channel(**parts)
        self.channel = channel
        self.url_w_subdir = self.channel.url(with_credentials=False)
        self.url_w_credentials = self.channel.url(with_credentials=True)
        # whether or not to try using the new, trimmed-down repodata
        self.repodata_fn = repodata_fn
        self._loaded = False

As of conda 4.3, a valid channel must contain a `noarch/repodata.json` and
                    associated `noarch/repodata.json.bz2` file, even if `noarch/repodata.json` is
                    empty. please request that the channel administrator create
                    `noarch/repodata.json` and associated `noarch/repodata.json.bz2` files.
                    $ mkdir noarch
                    $ echo '{}' > noarch/repodata.json
                    $ bzip2 -k noarch/repodata.json

                    You will need to adjust your conda configuration to proceed.
                    Use `conda config --show` to view your configuration's current state.
                    Further configuration help can be found at <%s>.
                    """) % (maybe_unquote(dirname(url)),
                            join_url(CONDA_HOMEPAGE_URL, 'docs/config.html'))

        elif status_code == 401:
            channel = Channel(url)
            if channel.token:
                help_message = dals("""
                The token '%s' given for the URL is invalid.

                If this token was pulled from anaconda-client, you will need to use
                anaconda-client to reauthenticate.

                If you supplied this token to conda directly, you will need to adjust your
                conda configuration to proceed.

                Use `conda config --show` to view your configuration's current state.
                Further configuration help can be found at <%s>.
               """) % (channel.token, join_url(CONDA_HOMEPAGE_URL, 'docs/config.html'))

            elif context.channel_alias.location in url:
                # Note, this will not trigger if the binstar configured url does

if k.endswith('.tar.bz2'):
                    packages[k] = v
                elif k.endswith('.conda'):
                    conda_packages[k] = v
    if not repodata:
        repodata = {
            "info": {
                "subdir": subdir,
                "arch": context.arch_name,
                "platform": context.platform,
            },
            "packages": packages,
            "packages.conda": conda_packages,
        }

    channel = Channel('https://conda.anaconda.org/dummy-channel/%s' % subdir)
    sd = SubdirData(channel)
    sd._process_raw_repodata_str(json.dumps(repodata))
    sd._loaded = True
    SubdirData._cache_[channel.url(with_credentials=True)] = sd

    index = {prec: prec for prec in precs or sd._package_records}
    r = Resolve(index, channels=(channel,))
    return r