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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 start_of_chunk(prev_tag, tag, prev_type, type_):
 """Checks if a chunk started between the previous and current word. Args: prev_tag: previous chunk tag. tag: current chunk tag. prev_type: previous type. type_: current type. Returns: chunk_start: boolean. """

    chunk_start = False

    if tag == 'B': chunk_start = True
    if tag == 'S': chunk_start = True

    if prev_tag == 'E' and tag == 'E': chunk_start = True
    if prev_tag == 'E' and tag == 'I': chunk_start = True
    if prev_tag == 'S' and tag == 'E': chunk_start = True
    if prev_tag == 'S' and tag == 'I': chunk_start = True
    if prev_tag == 'O' and tag == 'E': chunk_start = True
    if prev_tag == 'O' and tag == 'I': chunk_start = True

    if tag != 'O' and tag != '.' and prev_type != type_:
        chunk_start = True

    return chunk_start