How to concatenate elements(strings) of a list, between two specific list positions as identified by a regex?

Question

I have a long list of elements (thousands) which are strings, and need to capture and concatenate strings between two elements matched by a regex.

See below code, however, I am stuck on how to capture the text in between and concatenate the each element into one string?

my_list = ['this is a test element 1', 'I need to capture after this element','capture1','capture2', 'capture3','.........', 'I need to capture before this element' ]
my_reg = re.compile(r'I need to capture.+')

captured_text=[]
for i,element in enumerate(my_list):
    m=my_reg.match(element)
    if m:
        captured_text.append(my_list[i+1])

but i+1 is out of range

I hope to end up with a string capture1capture2capture3.....

Answer 1

match_indices = [i for i, s in enumerate(my_list) if my_reg.match(s)]
captured_text = my_list[min(match_indices)+1 : max(match_indices)]

The result:

>>> captured_text
['capture1', 'capture2', 'capture3', '.........']
>>> "".join(captured_text)
'capture1capture2capture3.........'