Detailed explanation of the use of lower and upper functions in python

I encountered a small problem today. I need to write a program to convert the irregular English names in the List into [capitalize the first letter and lowercase the rest]

The initial idea was to write a function to convert each name into uppercase. To process a name string [str], how to use map for batch processing

I have to say that the general idea is correct, but there are some problems in the detailed processing

At first, I wrote the name processing function like this:

[python] view plain copy
def change (name)  
    result = name[0].upper()  
    for a in name[1:len(name)]:  
        result = result + a.lower()

Then an error will be reported when running

[python] view plain copy
E:\PythonFile>python practice.py  
  File "practice.py", line 6  
    for a in name(1:len(name)-1) :  
                   ^  
SyntaxError: invalid syntax  
  
E:\PythonFile>python practice.py  
Traceback (most recent call last):  
  File "practice.py", line 11, in <module>  
    name_li = map (change, name_list)  
  File "practice.py", line 6, in change  
    for a in name(1,len(name)-1) :  
TypeError: &#39;str&#39; object is not callable  
  
E:\PythonFile>python practice.py  
Traceback (most recent call last):  
  File "practice.py", line 9, in <module>  
    name_li = map (change, name_list)  
  File "practice.py", line 5, in change  
    name[0] = name[0].upper()  
TypeError: &#39;str&#39; object does not support item assignment  
  
E:\PythonFile>python practice.py  
Traceback (most recent call last):  
  File "practice.py", line 10, in <module>  
    name_li = map (change, name_list)  
  File "practice.py", line 6, in change  
    name[0] = tmp  
TypeError: &#39;str&#39; object does not support item assignment  
  
E:\PythonFile>python  
Python 2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)] on win  
32  
Type "help", "copyright", "credits" or "license" for more information.  
>>> l = &#39;zxcv&#39;  
>>> print l[0]  
z  
>>> print l[0].upper  
<built-in method upper of str object at 0x02148740>  
>>> print l[0].upper()  
Z  
>>> z  
Traceback (most recent call last):  
  File "<stdin>", line 1, in <module>  
NameError: name &#39;z&#39; is not defined  
>>> ^Z  
  
  
E:\PythonFile>python practice.py  
Traceback (most recent call last):  
  File "practice.py", line 9, in <module>  
    name_li = map (change, name_list)  
  File "practice.py", line 6, in change  
    name[0] = tmp  
TypeError: &#39;str&#39; object does not support item assignment  
  
E:\PythonFile>python practice.py  
Traceback (most recent call last):  
  File "practice.py", line 13, in <module>  
    name_li = map (change, name_list)  
  File "practice.py", line 5, in change  
    tmp = chr(name[0])  
TypeError: an integer is required

After trying it a few times, I found that the general meaning is that string processing cannot be done in this way, so I checked Regarding the usage of upper() and lower(), I found that these two functions directly act on str, so there is no need to be so troublesome at all.

After modification:

[python] view plain copy
# practice.py  
# Change the first char in every name from lower type to upper type  
  
def change (name):  
    result =  name[0:1].upper()+name[1:len(name)].lower()  
    return result  
  
name_list = ['kzd','ysy','kcw','scr','ky']  
name_li = map (change, name_list)  
print name_l

Run result:

[python] view plain copy
E:\PythonFile>python practice.py  
['Kzd', 'Ysy', 'Kcw', 'Scr', 'Ky']

The error is that I tried to assign and replace the elements in the string, which is not allowed.

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