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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 get_config(key):
    '''
    Get an identicon configuration parameter.

    Precedance order is:
        - application config (`udata.cfg`)
        - theme config
        - default
    '''
    key = 'AVATAR_{0}'.format(key.upper())
    local_config = current_app.config.get(key)
    return local_config or getattr(theme.current, key, DEFAULTS[key])