How to remove all text between the outer parentheses in a string?

NOTE: \(.*\) matches the first ( from the left, then matches any 0+ characters (other than a newline if a DOTALL modifier is not enabled) up to the last ), and does not account for properly nested parentheses.

To remove nested parentheses correctly with a regular expression in Python, you may use a simple \([^()]*\) (matching a (, then 0+ chars other than ( and ) and then a )) in a while block using re.subn:

def remove_text_between_parens(text):
    n = 1  # run at least once
    while n:
        text, n = re.subn(r'\([^()]*\)', '', text)  # remove non-nested/flat balanced parts
    return text

Bascially: remove the (...) with no ( and ) inside until no match is found. Usage:

print(remove_text_between_parens('stuff (inside (nested) brackets) (and (some(are)) here) here'))
# => stuff   here

A non-regex way is also possible:

def removeNestedParentheses(s):
    ret = ''
    skip = 0
    for i in s:
        if i == '(':
            skip += 1
        elif i == ')'and skip > 0:
            skip -= 1
        elif skip == 0:
            ret += i
    return ret

x = removeNestedParentheses('stuff (inside (nested) brackets) (and (some(are)) here) here')
print(x)              
# => 'stuff   here'

See another Python demo

As mentioned before, you'd need a recursive regex for matching arbitrary levels of nesting but if you know there can only be a maximum of one level of nesting have a try with this pattern:

\((?:[^)(]|\([^)(]*\))*\)

• [^)(] matches a character, that is not a parenthesis (negated class).
• |\([^)(]*\) or it matches another ( ) pair with any amount of non )( inside.
• (?:...)* all this any amount of times inside ( )

Here is a demo at regex101

Before the alternation used [^)(] without + quantifier to fail faster if unbalanced.
You need to add more levels of nesting that might occure. Eg for max 2 levels:

\((?:[^)(]|\((?:[^)(]|\([^)(]*\))*\))*\)

Another demo at regex101