如何从argparse的输入中获取字符串并将其用作对象

Question

I am trying to create a program that reads a string off an argparse input and uses that string to call a certain object and use that object for the rest of the function.

 #!/usr/bin/python
import argparse

class car:
    def __init__(self, color, year):
        self.color = color
        self.year = year

Beatle = car("blue", 1973)

parser = argparse.ArgumentParser()
parser.add_argument("--vehicleType")
args = parser.parse_args()

print("This "+args.vehicleType+ " is nice")
print("It was made:")
print(2018-args.vehicleType.year)
print("years ago")

However, I keep getting back this error:

   Traceback (most recent call last):
  File "./test.py", line 17, in <module>
    print(2018-args.vehicleType.year)
AttributeError: 'str' object has no attribute 'year'

I think the program is reading args.vehicleType as a string, while I want to read it in as an object. How do I get around this? -Cheers, and thanks in advance! ~O. Fried

Answer 1

Would it be possible to actually create the object after? Something along these lines:

#!/usr/bin/python
import argparse
class car:
    def __init__(self, color, year, type):
        self.color = color
        self.year = year
        self.type = type

parser = argparse.ArgumentParser()
parser.add_argument("--vehicleType") # Accept the argument as vehicle type.
args = parser.parse_args()

Beatle = car("blue", 1973, str(args.vehicleType)) # Now create the object.

print("This " + Beatle.type+ " is nice") # Use it here.
print("It was made:")
print(2018-Beatle.year) # And here.
print("years ago.")

Answer 2

Make a dictionary of cars

adict = {'beattle': car('blue',1973), 'ford': car('black', 1907),...}

yourcar = adict[args.vehicleType]
print(yourcar.year)