class Document:
    """
    This class is an abstraction for document and holds one or many paragraphs.
    Attributes:
        id: uniques identifier for the document in the corpus
        paras: list of Paragraph (see Paragraph class)
    """
    def __init__(self, _id, paras):
        """
        Constructor for Document class
        """
        self._id = _id
        self.paras = paras
        size = 0
        for para in paras:
            size += para.size
        self.size = size