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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 init_cli(self, app):
 """ Initialize the Flask CLI support in case it was enabled for the app. Works with both Flask>=1.0's CLI support as well as the backport in the Flask-CLI package for Flask<1.0. """

        # in case click isn't installed after all
        if click is None:
            raise RuntimeError('Cannot import click. Is it installed?')
        # only add commands if we have a click context available
        from .cli import add_commands
        add_commands(app.cli, self)