As you can see in these examples of file handling, the function open takes at least two arguments. The first is obviously the filename, and the second is a string describing the way in which the file will be used. There are several such modes for opening files. The basic ones are as follows:
with open('file1.dat','r') as ... # read only
with open('file2.dat','r+') as ... # read/write
with open('file3.dat','rb') as ... # read in byte mode
with open('file4.dat','a') as ... # append (write to the end of the file)
with open('file5.dat','w') as ... # (over-)write the file
with open('file6.dat','wb') as ... # (over-)write the file in byte mode
The modes 'r', 'r+', and 'a' require that the file exists, whereas 'w' will create a new file if no file with that name...
