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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 dev():

 """Define dev stage"""

    env.roledefs = {
        'web': ['192.168.1.2'],
        'lb': ['192.168.1.2'],
    }
    env.user = 'vagrant'
    env.backends = env.roledefs['web']
    env.server_name = 'django_search_model-dev.net'
    env.short_server_name = 'django_search_model-dev'
    env.static_folder = '/site_media/'
    env.server_ip = '192.168.1.2'
    env.no_shared_sessions = False
    env.server_ssl_on = False
    env.goal = 'dev'
    env.socket_port = '8001'
    env.map_settings = {}
    execute(build_env)