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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 show(ctx, project_id, backend):
 """ Shows the details of the given project id. """

    try:
        project = ctx.obj['projects_db'].get(project_id, backend)
    except IOError:
        raise Exception("Error: the projects database file doesn't exist. "
                        "Please run `taxi update` to create it")

    if project is None:
        ctx.obj['view'].err(
            "Could not find project `%s`" % (project_id)
        )
    else:
        ctx.obj['view'].project_with_activities(project)