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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 make_server( server_class, handler_class, authorizer_class, filesystem_class, host_port, file_access_user=None, **handler_options):
 """make server instance :host_port: (host, port) :file_access_user: 'spam' handler_options: * timeout * passive_ports * masquerade_address * certfile * keyfile """

    from . import compat
    if isinstance(handler_class, compat.string_type):
        handler_class = import_class(handler_class)

    if isinstance(authorizer_class, compat.string_type):
        authorizer_class = import_class(authorizer_class)

    if isinstance(filesystem_class, compat.string_type):
        filesystem_class = import_class(filesystem_class)

    authorizer = authorizer_class(file_access_user)
    handler = handler_class
    for key, value in handler_options.items():
        setattr(handler, key, value)
    handler.authorizer = authorizer
    if filesystem_class is not None:
        handler.abstracted_fs = filesystem_class
    return server_class(host_port, handler)