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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def as_variable(obj, name=None) -> 'Union[Variable, IndexVariable]': """Convert an object into a Variable. Parameters obj : object Object to convert into a Variable. - If the object is already a Variable, return a shallow copy. - Otherwise, if the object has 'dims' and 'data' attributes, convert it into a new Variable. - If all else fails, attempt to convert the object into a Variable by unpacking it into the arguments for creating a new Variable. name : str, optional If provided: - `obj` can be a 1D array, which is assumed to label coordinate values along a dimension of this given name. - Variables with name matching one of their dimensions are converted into `IndexVariable` objects. Returns ------- var : Variable The newly created variable. """

    from .dataarray import DataArray

    # TODO: consider extending this method to automatically handle Iris and
    if isinstance(obj, DataArray):
        # extract the primary Variable from DataArrays
        obj = obj.variable

    if isinstance(obj, Variable):
        obj = obj.copy(deep=False)
    elif isinstance(obj, tuple):
        try:
            obj = Variable(*obj)
        except (TypeError, ValueError) as error:
            # use .format() instead of % because it handles tuples consistently
            raise error.__class__('Could not convert tuple of form '
                                  '(dims, data[, attrs, encoding]): '
                                  '{} to Variable.'.format(obj))
    elif utils.is_scalar(obj):
        obj = Variable([], obj)
    elif isinstance(obj, (pd.Index, IndexVariable)) and obj.name is not None:
        obj = Variable(obj.name, obj)
    elif isinstance(obj, (set, dict)):
        raise TypeError(
            "variable %r has invalid type %r" % (name, type(obj)))
    elif name is not None:
        data = as_compatible_data(obj)
        if data.ndim != 1:
            raise MissingDimensionsError(
                'cannot set variable %r with %r-dimensional data '
                'without explicit dimension names. Pass a tuple of '
                '(dims, data) instead.' % (name, data.ndim))
        obj = Variable(name, data, fastpath=True)
    else:
        raise TypeError('unable to convert object into a variable without an '
                        'explicit list of dimensions: %r' % obj)

    if name is not None and name in obj.dims:
        # convert the Variable into an Index
        if obj.ndim != 1:
            raise MissingDimensionsError(
                '%r has more than 1-dimension and the same name as one of its '
                'dimensions %r. xarray disallows such variables because they '
                'conflict with the coordinates used to label '
                'dimensions.' % (name, obj.dims))
        obj = obj.to_index_variable()

    return obj