...<name@domain.com>...

>>> import re
>>> line = "should we use regex more often? let me know at  321dsasdsa@dasdsa.com.lol"
>>> match = re.search(r'[w.-]+@[w.-]+', line)
>>> match.group(0)
'321dsasdsa@dasdsa.com.lol'

>>> line = "why people don't know what regex are? let me know 321dsasdsa@dasdsa.com.lol   dssdadsa dadaads@dsdds.com"
>>> match = re.findall(r'[w.-]+@[w.-]+', line)
>>> match
['321dsasdsa@dasdsa.com.lol', 'dadaads@dsdds.com']

>>> import re
>>> text = "this is an email la@test.com, it will be matched, x@y.com will not, and test@test.com will"
>>> match = re.findall(r'[w-._+%]+@test.com',text) # replace test.com with the domain you're looking for, adding a backslash before periods
>>> match
['la@test.com', 'test@test.com']

import re
line = "why people don't know what regex are? let me know asdfal2@als.com, Users1@gmail.de "
       "Dariush@dasd-asasdsa.com.lo,Dariush.lastName@someDomain.com"
match = re.findall(r'[w.-]+@[w.-]+', line)
for i in match:
    print(i)

print(match)

text = "blabla <hello@world.com>><123@123.at> <huhu@fake> bla bla <myname@some-domain.pt>"

# 1. find all potential email addresses (note: < inside <> is a problem)
matches = re.findall('<S+?>', text)  # ['<hello@world.com>', '<123@123.at>', '<huhu@fake>', '<myname@somedomain.edu>']

# 2. apply email regex pattern to string inside <>
emails = [ x[1:-1] for x in matches if re.match(r"(^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+.[a-zA-Z0-9-.]+$)", x[1:-1]) ]
print emails   # ['hello@world.com', '123@123.at', 'myname@some-domain.pt']