DatabaseError：对sql对象执行失败'：要执行的第一个参数必须是字符串或Unicode查询

Question

server = "UAT101"
db = "mydb"
con = pyodbc.connect('DRIVER={SQL Server};SERVER=' + server + ';DATABASE=' + db +';Uid=uat101_read;Pwd=*****')

max_week = pd.read_sql("select max(FWEEK) from mytable", con).astype('int')
max_week = max_week.iloc[0].astype('str')

min_week = pd.read_sql("select min(FWEEK) from SOE_DC_ML_8K.dbo.RAWDATA_DC_CONSOLIDATED where FWEEK in (select distinct top 2 FWEEK from mytable order by FWEEK desc)", con).astype('int')
min_week = min_week.iloc[0].astype('str')

query = "Select [FWEEK],[DPS_NUM] from mytable where (fweek = '"+max_week+"' or (fweek = '"+min_week+"' and NEW_DPS_FLG = '1'))"

df = pd.read_sql(query, con)

  

DatabaseError：在sql上执行失败-选择   [FWEEK]，[DPS_NUM]，[COMMODITYDESC]，[SYST ...名称：0，dtype：object'：   要执行的第一个参数必须是字符串或Unicode查询。

执行df = pd.read_sql(query, con)语句时出现错误