[4/30/18, 5:49:51 PM] ‪+11 11 111 1111: Thanks for the recommendation.
[4/30/18, 5:51:21 PM] Joe Johnson: It's a pleasure to know you!
[4/30/18, 6:00:55 PM] ‪+11 1 11 1111 1111: Nice!
[4/30/18, 6:22:01 PM] ‪+1 (111) 111‑111: sure.. I will look into.

date_regex = re.compile(r'(d+/d+/d+)')
date = date_regex.findall(watsup_content)
time_regex = re.compile(r'(d{1,2}:d{2}:d{2} AM|d{1,2}:d{2}:d{2} PM)')
time = time_regex.findall(watsup_content)

import re

with open('myfile.txt', 'r') as f:
    content = f.readlines()

date_regex = re.compile(r'(d+/d+/d+)')
time_regex = re.compile(r'(d{1,2}:d{2}:d{2} AM|d{1,2}:d{2}:d{2} PM)')

for line in content:
    print(line)
    date = date_regex.findall(line)
    time = time_regex.findall(line)
    content = line.split(':')[-1].strip()
    author = line.split(']')[-1].split(':')[0].strip()
    print(date)
    print(time)
    print(author)
    print(content)
    print('---')

[4/30/18, 5:49:51 PM] ‪+11 11 111 1111: Thanks for the recommendation.

['4/30/18']
['5:49:51 PM']
‪+11 11 111 1111
Thanks for the recommendation.
---
[4/30/18, 5:51:21 PM] Joe Johnson: It's a pleasure to know you!

['4/30/18']
['5:51:21 PM']
Joe Johnson
It's a pleasure to know you!
---
[4/30/18, 6:00:55 PM] ‪+11 1 11 1111 1111: Nice!

['4/30/18']
['6:00:55 PM']
‪+11 1 11 1111 1111
Nice!
---
[4/30/18, 6:22:01 PM] ‪+1 (111) 111‑111: sure.. I will look into.

['4/30/18']
['6:22:01 PM']
‪+1 (111) 111‑111
sure.. I will look into.
---