Calculating the factorial value of a given number

silnia.py

from decimal import *
import sys
setcontext(Context(prec=3,capitals=0))
inputValue = input("Enter n: ") # Enter the value of n
try:
    integer = int(inputValue) # Convert a string to an integer
    if(integer >= 0): # If the integer is non-negative
        factorialValue = Decimal(1) # Set the initial value
        for i in range(1,integer+1): # For every positive integer less than n
            factorialValue *= i # Multiple the value by the integer
        if(factorialValue > sys.float_info.max):  # If the factorial value is greater than maximum float value...
            print("Factorial value:", factorialValue) # ...display value in the E-notation
        else:
            print("Factorial value: {0:.2f}".format(float(factorialValue))) # Otherwise, display value as float with 2 decimal places
    else:
        print("Entered value is not a natural number!") # Show error if the integer is negative
except ValueError:
    print("Entered value is not a natural number!") # Show error if string is not an integer
except Overflow:
    print("Overflow Error: Value is too large!") # Show error if value is to large for Decimal module
except:
    print("Unknown error!")