Warum funktioniert mein Code nicht und was bedeutet dieser Fehler?

import random
initial_val = str(10)
attr_c1_stre = ("Character 1's Strength: ",str(random.randint(1,12)/random.randint(1,4)     + initial_val))
attr_c1_skill = ("Character 1's Skill: ",str(random.randint(1,12)/random.randint(1,4) +     initial_val))
attr_c2_stre = ("Character 2's Strength: ",str(random.randint(1,12)/random.randint(1,4)     + initial_val))
attr_c2_skill = ("Character 2's Skill: ",str(random.randint(1,12)/random.randint(1,4) +     initial_val))
print("attr_c1_stre", "\nattr_c1_skil", "\n\nattr_c2_stre","\nattr_c2_skill")
file = open("Attribute.txt", "w")
file.write(attributes)
file.close()
input("\n\nPress enter to exit")

Das sagt IDLE:

Traceback (most recent call last):
  File "H:\Python task - dice\Task 2\python codefor task 2].py", line 3, in <module>
    attr_c1_stre = ("Character 1's Strength: ",str(random.randint(1,12)/random.randint(1,4) + initial_val))
TypeError: unsupported operand type(s) for +: 'float' and 'str'

Danke vielmals