Write a python program to: Read two strings, then put the second string in the middle ofthe first string. And finally Write the new string in a new file.

Sure, here is a simple Python program that accomplishes this:

# Step 1: Read two strings
str1 = input("Enter the first string: ")
str2 = input("Enter the second string: ")

# Step 2: Put the second string in the middle of the first string
middle_index = len(str1) // 2
new_str = str1[:middle_index] + str2 + str1[middle_index:]

# Step 3: Write the new string in a new file
with open("new_file.txt", "w") as f:
    f.write(new_str)

This program first reads two strings from the user. It then calculates the middle index of the first string and inserts the second string at this position. Finally, it writes the resulting string to a new file named "new_file.txt".