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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 ready(self):
 """Perform application initialization."""

        # Initialize the type extension composer.
        from . composer import composer
        composer.discover_extensions()

        is_migrating = sys.argv[1:2] == ['migrate']
        if is_migrating:
            # Do not register signals and ES indices when:
            # * migrating - model instances used during migrations do
            #   not contain the full functionality of models and things
            #   like content types don't work correctly and signals are
            #   not versioned so they are guaranteed to work only with
            #   the last version of the model
            return

        # Connect all signals
        from . import signals  # pylint: disable=unused-import

        # Register ES indices
        from . builder import index_builder