import re
s = 'Hello from shubhamg199630@gmail.com to priya@yahoo.com about the meeting @2PM'
# S matches any non-whitespace character
# @ for as in the Email
# + for Repeats a character one or more times
lst = re.findall('S+@S+', s)
print(lst)
#['shubhamg199630@gmail.com', 'priya@yahoo.com']