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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 is_default(name=None, index=None):
 """ returns True if the specified configuration is the default one """


    if not is_configured():
        raise JutException('No configurations available, please run `jut config add`')

    count = 1
    for configuration in _CONFIG.sections():

        if index != None:
            if _CONFIG.has_option(configuration, 'default') and count == index:
                return True

        if name != None:
            if _CONFIG.has_option(configuration, 'default') and configuration == name:
                return True

        count += 1

    return False