def get_sentiment(text, analyzer):
    """Compute the sentiment label of a document
    based on a given VADER analyzer.
    
    Args:
        text: A given text document.
        analyzer: VADER analyser for sentiment analysy.

    Returns:
        A string representing the identified sentiment
        based on the compound score returned by the analyser.
        Possible values are: 'Positive', 'Negative' or
        'Neutral'.

    """

    compound_score = analyzer.polarity_scores(text)['compound']
    
    if compound_score  >= 0.05:
        return 'positive'
    
    if compound_score <= -0.05:
        return 'negative'
    
    return 'neutral'