Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Temple name | Posthumous name | Family name (in bold) and personal name | Reign | Era names and their year ranges | Notes |
| --- | --- | --- | --- | --- | --- |
| Shizu\n始祖 | Emperor Wulie\n武烈皇帝 | Sun Jian\n孫堅 | (N/A) | (N/A) | Sun Jian's temple and posthumous names were granted posthumously by Sun Quan. |
| (N/A) | Prince Huan of Changsha\n長沙桓王 | Sun Ce\n孫策 | (N/A) | (N/A) | Sun Ce's posthumous name was granted posthumously by Sun Quan. |
| Taizu\n太祖 | Emperor Da\n大皇帝 | Sun Quan\n孫權 | 222-252 | Huangwu\n黃武 (222-229)\nHuanglong\n黃龍 (229-231)\nJiahe\n嘉禾 (232-238)\nChiwu\n赤烏 (238-251)\nTaiyuan\n太元 (251-252)\nShenfeng\n神鳳 (252) | Sun Quan adopted the era name "Huangwu" in 222 after declaring independence from Wei. However, he continued ruling under the title "King of Wu" and did not proclaim himself emperor until 229. |
| (N/A) | (N/A) | Sun Liang | 252-258 | Jianxing\n建興 (252-253)\nWufeng\n五鳳 (254-256)\nTaiping\n太平 (256-258) | Sun Liang became "Prince of Kuaiji" (會稽王) after he was dethroned by Sun Chen in 258. In 260, his successor Sun Xiu further demoted him to "Marquis of Houguan" (侯官侯). |
| (N/A) | Emperor Jing\n景皇帝 | Sun Xiu\n孫休 | 258-264 | Yong'an\n永安 (258-264) |  |
| (N/A) | Emperor Wen\n文皇帝 | Sun He\n孫和 | (N/A) | (N/A) | Sun He's posthumous name was granted posthumously by Sun Hao. |
| (N/A) | (N/A) | Sun Hao\n孫皓 | 264-280 | Yuanxing\n元興 (264-265)\nGanlu\n甘露 (265-266)\nBaoding\n寶鼎 (266-269)\nJianheng\n建衡 (269-271)\nFenghuang\n鳳凰 (272-274)\nTiance\n天冊 (275-276)\nTianxi\n天璽 (276)\nTianji\n天紀 (277-280) | Sun Hao held the title of "Marquis of Wucheng" (烏程侯) before he became emperor in 264. In 280, after surrendering to the Jin dynasty, he was granted the title of granted the title of "Marquis of Guiming" (歸命侯) by Sima Yan. He is also sometimes referred to as "Emperor Mo of Wu" (吳末帝), which literally means "last emperor of Wu". |
Question:
how many eastern wu rules were there?
Answer:
7