How can I make a def function with my "if" statements?

We were asked to make a function named temperature conversions that accepts an integer argument called temperature, a secondary string parameter called input unit, and a third string parameter called output unit. input unit specifies the unit of the value in temperature. This function shall convert and return the value in temperature to the unit specified in target unit. Both unit arguments shall be one of “C”, “K”, or “F”.

I came up with a bunch of if statements and it works, but I am not able to create the function that works.

input_unit, target_unit = input("Input the temperature and the unit to convert      it to: [e.g. 45c f > valid Units: C,K,F: ").split()
degree = int(input_unit[:-1])
i_unit = input_unit[-1].upper()
o_unit = target_unit.upper()

if i_unit == "C" and o_unit == "F":
  result = int((1.8 * degree) + 32)
  print("{:0.2f}°{} ⇒ {:0.2f}°{}".format(degree,i_unit,result,o_unit))
elif i_unit == "C" and o_unit == "K":
  result = int(degree + 273.15)
  print("{:0.2f}°{} ⇒ {:0.2f}°{}".format(degree,i_unit,result,o_unit))
elif i_unit == "F" and o_unit == "K":
  result = int(((degree * 1.8) +32)+ 273.15)
  print("{:0.2f}°{} ⇒ {:0.2f}°{}".format(degree,i_unit,result,o_unit))
elif i_unit == "F" and o_unit == "C":
  result = int((degree  - 32) / 1.8)
  print("{:0.2f}°{} ⇒ {:0.2f}°{}".format(degree,i_unit,result,o_unit))
elif i_unit == "K" and o_unit == "C":
  result = int(degree - 273.15)
  print("{:0.2f}°{} ⇒ {:0.2f}°{}".format(degree,i_unit,result,o_unit))
elif i_unit == "K" and o_unit == "F":
  result = int(((degree  - 273.15) - 32) / 1.8)
  print("{:0.2f}°{} ⇒ {:0.2f}°{}".format(degree,i_unit,result,o_unit))
else:
  while True:
    input_unit, target_unit = input("Input the temperature and the unit to  convert it to?: ").split()
    if input_unit[-1].upper() != "C" or target_unit.upper() != "F":
      print("You enterd an invalid unit. Please enter again: ")

Here I advise you to decompose your program in several steps first you ask for the temperature, then you make the conversion with a function and then you display the results.

def temperatureConversions(degree, i_unit, o_unit):
    if i_unit == "C" and o_unit == "F":
        return int((1.8 * degree) + 32)
    elif i_unit == "C" and o_unit == "K":
        return int(degree + 273.15)
    elif i_unit == "F" and o_unit == "K":
        return int(((degree * 1.8) +32)+ 273.15)
    elif i_unit == "F" and o_unit == "C":
        return int((degree  - 32) / 1.8)
    elif i_unit == "K" and o_unit == "C":
        return int(degree - 273.15)
    elif i_unit == "K" and o_unit == "F":
        return int(((degree  - 273.15) - 32) / 1.8)

valueCorrect = False
while(not valueCorrect):
    degree = input("Please enter a temperature (ex: 47C):\n")
    o_unit = input("Please enter the output unit desired(ex: C, F, K):")
    if(degree[:-1].isdigit()):
        i_unit, degree = degree[-1], int(degree[:-1])
        if(i_unit and o_unit in ['C', 'F', 'K']):
            valueCorrect = True
        else:
           print("Please write correct values of unit !") 
    else:
        print("Please write correct values of temperature !")

resultConversion = temperatureConversions(degree, i_unit, o_unit)

print("{:0.2f}°{} ⇒ {:0.2f}°{}".format(degree,i_unit,resultConversion,o_unit))

Confirm me that it works for you.