getting source line number

[Skaperen]

is there a way to get the source file line number in some code?  for example:

from __future__ import print_function

# print a message with source line number

n = get_source_code_file_line_number()
n += 2
print('now printing at line',str(n))

Output:
now printing at line 6

OR

from __future__ import print_function
for n in range(3)
    print('now printing at line',str(get_source_code_file_line_number()))
    print('now printing at line',str(get_source_code_file_line_number()))

Output:
now printing at line 2
now printing at line 3
now printing at line 2
now printing at line 3
now printing at line 2
now printing at line 3

it's ok if it is based on starting at 1 instead of 0.