为什么不删除所选的值？Pandas

Question

为什么不删除所选的值

data = []
data = pd.read_csv(r'summary.csv', low_memory=False, header = None, sep = ',')
to_drop= ['[-11057] Not Enough Values For Calculation',str]
data = data[~data[:].isin(to_drop)]
data = data.dropna(inplace = True)
data.shape

它仍然没有删除选定的值，为什么