parenthessis content

def in_parentheses(mystr):
    count=-1
    flag1=0
    flag2=0
    for char in mystr:
        count+=1
        if char=="(":
            flag1=count
        elif char==")":
            flag2=count
    if flag1!=0 and flag2!=0:        
        return mystr[flag1+1:flag2]
    else:
        return ""