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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 paster(opts):
 """Run a paster command from the current directory Usage: Options: -s --site=NAME Specify a site to run this paster command on [default: primary] -d --detach Run the resulting container in the background You must be inside a datacats environment to run this. The paster command will run within your current directory inside the environment. You don't need to specify the --plugin option. The --config option also need not be specified. """

    environment = Environment.load('.')
    environment.require_data()
    environment.start_supporting_containers()

    if not opts['COMMAND']:
        opts['COMMAND'] = ['--', 'help']

    assert opts['COMMAND'][0] == '--'
    return environment.interactive_shell(
        opts['COMMAND'][1:],
        paster=True,
        detach=opts['--detach']
        )