Python pandas 有效地删除 UserWarning 和循环

可以说我有类似的代码：

import pandas as pd

df=pd.DataFrame({'Name': [ 'Jay Leno', 'JayLin', 'Jay-Jameson', 'LinLeno', 'Lin Jameson', 'Python Leno', 'Python Lin', 'Python Jameson', 'Lin Jay', 'Python Monte'],
                 'Class': ['Rat','L','H','L','L','H', 'H','L','L','Circus']})
df['status']=''

pattern1=['^Jay(\s|-)?(Leno|Lin|Jameson)$','^Python(\s|-)?(Jay|Leno|Lin|Jameson|Monte)$','^Lin(\s|-)?(Leno|Jay|Jameson|Monte)$' ]
pattern2=['^Python(\s|-)?(Jay|Leno|Lin|Jameson|Monte)$' ]
pattern3=['^Lin(\s|-)?(Leno|Jay|Jameson|Monte)$' ]

for i in range(len(pattern1)):
    df.loc[df.Name.str.contains(pattern1[i]),'status'] = 'A'

for i in range(len(pattern2)):
    df.loc[df.Name.str.contains(pattern2[i]),'status'] = 'B'

for i in range(len(pattern3)):
    df.loc[df.Name.str.contains(pattern3[i]),'status'] = 'C'

print (df)

哪个打印：

C:\Python33\lib\site-packages\pandas\core\strings.py:184: UserWarning: This pattern has match groups. To actually get the groups, use str.extract.
  " groups, use str.extract.", UserWarning)
    Class            Name status
0     Rat        Jay Leno      A
1       L          JayLin      A
2       H     Jay-Jameson      A
3       L         LinLeno      C
4       L     Lin Jameson      C
5       H     Python Leno      B
6       H      Python Lin      B
7       L  Python Jameson      B
8       L         Lin Jay      C
9  Circus    Python Monte      B

[10 rows x 3 columns]

我的问题是如何消除错误以及是否有一种方法可以使用更少的代码更有效地循环？我知道有一种叫做列表理解的东西，但我对如何使用它们感到困惑。

我知道可以用以下方法抑制错误

pd.options.mode.chained_assignment = None

Use 非捕获括号 http://docs.python.org/2/library/re.html#regular-expression-syntax (?:...):

pattern1=['^Jay(?:\s|-)?(?:Leno|Lin|Jameson)$','^Python(?:\s|-)?(?:Jay|Leno|Lin|Jameson|Monte)$','^Lin(?:\s|-)?(?:Leno|Jay|Jameson|Monte)$' ]
pattern2=['^Python(?:\s|-)?(?:Jay|Leno|Lin|Jameson|Monte)$' ]
pattern3=['^Lin(?:\s|-)?(?:Leno|Jay|Jameson|Monte)$' ]

警告来自这段代码 https://github.com/pydata/pandas/blob/master/pandas/core/strings.py#L182:

    if regex.groups > 0:
        warnings.warn("This pattern has match groups. To actually get the"
                      " groups, use str.extract.", UserWarning)

所以只要没有群体，就没有警告。