[Python] Calling a function with default value for arguments

In Python, how can I call a function using the default value of an argument? I know it can be done just not passing the parameter when you call the function, but I would prefer to pass the variable through the function though.

Having these two functions:

def A(argA1=defValA1, argA2=defValA2, argA3=defValA3):
argB1val=K*argA1
argB2val=K*argA2
argB3val=K*argA3
B(argB1=argB1val, argB2=argB2val,argB3=argB3val)

def B(argB1=defValB1, argB2=defValB2, argB3=defValB3):
print("First argument: "+argB1)
print("Second argument: "+argB2)
print("Third argument: "+argB3)


If I call A() with all the arguments, there's no problem:

Main:

A(argA1val, argA2val, argA3val)


But what if I call A() with some missing arguments?

Main:

A(argA1val)


In this case, inside the A() function, B() will be called taking the default values for the last two:

B(argB1= K*argA1, argB2= K* defValA2, argB3= K* defValA3)


However, I’d like to call B() using the default values of their last two arguments, something like:

B(argB1= K*argA1, argB2=defValB2, argB3=defValB3)


So, I would like A() to be something like:

def A(argA1=defValA1, argA2=defValA2, argA3=defValA3):

if (argA1==defValA1):
argB1val=B.getDefaultValue("argB1")
else:
argB1val=K*argA1

if (argA2==defValA2):
argB2val=B.getDefaultValue("argB2")
else:
argB2val=K*argA2

if (argA3==defValA3):
argB3val=B.getDefaultValue("argB3")
else:
argB3val=K*argA3

B(argB1=argB1val,argB2=argB2val,argB3=argB3val)


Otherwise, I’d need to do something like:

def A(argA1=defValA1, argA2=defValA2, argA3=defValA3):

if (argA1==defValA1 && argA2!=defValA2 && argA3!=defValA3):

argB2val=K*argA2
argB3val=K*argA3
B(argB1= defValB1, argB2=argB2val,argB3=argB3val)

if (argA1!=defValA1 && argA2==defValA2 && argA3!=defValA3):

argB1val=K*argA1
argB3val=K*argA3
B(argB1=argB1val, argB2= defValB2,argB3=argB3val)

if (argA1!=defValA1 && argA2!=defValA2 && argA3==defValA3):

argB1val=K*argA1
argB2val=K*argA2
B(argB1= argB1val, argB2=argB2val,argB3= defValB1)

if (argA1==defValA1 && argA2==defValA2 && argA3!=defValA3):

argB3val=K*argA3
B(argB1= defValA1, argB2= defValA2,argB3=argB3val)

# etc.


Having even a lot more combinations if we have more parameters.

Does anyone know if there's a way to get the default value of a parameter to be passed in a function?

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