# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
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# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


class Loader(object):
    """
    Base class for ARIA loaders.

    Loaders extract a document by consuming a document source.

    Though the extracted document is often textual (a string or string-like
    data), loaders may provide any format.
    """

    def open(self):
        pass

    def close(self):
        pass

    def load(self):
        raise NotImplementedError