If i have a string:
txt = "Good-bye my friend"
txt = "Good bye my friend"
string.replace(s, old, new[, maxreplace]) Return a copy of string s with all occurrences of substring old replaced by new. If the optional argument maxreplace is given, the first maxreplace occurrences are replaced.
So replace your hyphen with a space:
txt = txt.replace('-', ' ')