Script to remove some unwanted character from a string. Basic string manipulation

string_manipulation.py

out_file = open("out_file.txt","w")

with open('formulas.txt','r') as fil:
    for lin in fil:
        #Here, '+' is the unwanted character at the 0th position. Edit accordingly for other characters
        if(lin[0] == "+"):
            new_line = lin[1:]
            print new_line
            
        else:
            new_line = lin
        
        #Had to add a "dvs ~ " to each of my formulas in this case. Edit accordingly.
        new_line = "dvs ~ " + new_line
        new_form.write(new_line)

new_form.close()