Python, with usage

 First, what With statement is?

　　There are some tasks, you may need to set in advance, and afterwards do the cleanup work. For this scenario, Python with statement provides a very convenient approach. A good example is the file handle, you need to obtain a file handle to read data from the file, and then close the file handle.

If not with the statement, as follows:

file =open('1.txt', 'r', encoding="utf-8")
ret = file.read()
print(ret)
file.close()

There are two issues:

One may forget to close the file handle; 
the second is the occurrence of abnormal data file read, without any treatment.

This time is a go with the time. In addition to a more elegant syntax, with also a good handle exceptions context of the environment.

with open('1.txt', encoding="utf-8") as file:
    print(file.read())