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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 validate_words(word_list):
    '''
    Checks for each edited word in word_list if that word is a valid english word.abs
    Returns all validated words as a set instance.
    '''
    if word_list is None:
        return {}
    elif isinstance(word_list, list):
        if not word_list:
            return {}
        else:
            return set(word for word in word_list if word in WORD_DISTRIBUTION)
    else:
        raise InputError("list variable not passed as argument to validate_words")