有没有更短的编写逗号代码的方法？

Question

I am working on the practice projects in chapter 4 of Automate the boring stuff with Python .
In the Comma Code 'practice projects' , it asks you to write a function that takes a list value as an argument and returns a string with all the items separated by a comma and a space, with and inserted before the last item.

Is there a shorter way to write this code?

I have defined my function and used a for loop with range(len(list)) to iterate over the index of the list.

then I named my list and added some items to it.

I finished by calling the list.

 def carpenter(Powertools):
  for i in range(len(Powertools)-1):
    print(Powertools[i] + ',', end='')
 ToolBox = ['hammer','chisel','wrench','measuring tape', 'screwdriver']
 carpenter(ToolBox)
 print(' and ' + ToolBox[-1])

The output gave me the list items I wanted, with and inserted by the last item.
But I was wondering, is there a shorter way to write this code?

Answer 1

You can use a list comprehension inside join like this and append and followed by last item.

', '.join(x for x in ToolBox[:-1]) + ' and ' + ToolBox[-1]

Putting this to function can be done like this,

def carpenter(power_tools):

    return ', '.join(x for x in power_tools[:-1]) + ' and ' + power_tools[-1]

tool_box = ['hammer','chisel','wrench','measuring tape', 'screwdriver']

joined = carpenter(tool_box)

print(joined) # hammer, chisel, wrench, measuring tape and screwdriver

Note that I have changed the variable names following PEP-8.

Also, there is no need for comprehension, you can do something like this for the same result.

def carpenter(power_tools):

    return ', '.join(power_tools[:-1]) + ' and ' + power_tools[-1]

tool_box = ['hammer','chisel','wrench','measuring tape', 'screwdriver']

joined = carpenter(tool_box)

print(joined) # hammer, chisel, wrench, measuring tape and screwdriver

Answer 2

Use join() to make comma separated list and slice list until second last element and use string .format() for for combining last element

def carpenter(Powertools):
  finalresult=",".join(Powertools[:-1])
  print('{} and {}'.format(finalresult,Powertools[-1]))


ToolBox = ['hammer','chisel','wrench','measuring tape', 'screwdriver']
carpenter(ToolBox)

Result:

hammer,chisel,wrench,measuring tape and screwdriver

Answer 3

This should work:

def carpenter(powertools):
    return ','.join(powertools[:-1]) + ' and ' + powertools[-1]