Python 3.5.2 (default, Nov 17 2016, 17:05:23) 
[GCC 5.4.0 20160609] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 
>>> 
>>> string = "code"
>>> z = 35
>>> 
>>> print("My %s is %d lines long." % (string, z))
My code is 35 lines long.
>>> 
>>> p = 3.141592
>>> 
>>> print("Pi is about %f" % p)
Pi is about 3.141592
>>> 
>>> print("Pi is about %.2f" % p)
Pi is about 3.14
>>> 
>>> print("Pi is about %.4f" % p)
Pi is about 3.1416
>>> 
>>> 
>>> num_lst = [234.575742, 14.46574, 8.231235, 19.4239823928398]
>>> 
>>> for num in num_lst:
...     print("lining up numbers: %f" % num)
... 
lining up numbers: 234.575742
lining up numbers: 14.465740
lining up numbers: 8.231235
lining up numbers: 19.423982
>>> 
>>> 
>>> for num in num_lst:
...     print("lining up numbers: %.3f" % num)
... 
lining up numbers: 234.576
lining up numbers: 14.466
lining up numbers: 8.231
lining up numbers: 19.424
>>> 
>>> 
>>> for num in num_lst:
...     print("lining up numbers: %7.3f" % num)
... 
lining up numbers: 234.576
lining up numbers:  14.466
lining up numbers:   8.231
lining up numbers:  19.424
>>> 
>>> 
>>> 
>>>     print("lining up numbers: %6.3f" % num)
  File "<stdin>", line 1
    print("lining up numbers: %6.3f" % num)
    ^
IndentationError: unexpected indent
>>> 
>>> for num in num_lst:
...     print("lining up numbers: %6.3f" % f)
... 
Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
NameError: name 'f' is not defined
>>> 
>>> 
>>> for num in num_lst:
...     print("lining up numbers: %6.3f" % num)
... 
lining up numbers: 234.576
lining up numbers: 14.466
lining up numbers:  8.231
lining up numbers: 19.424
>>> 
>>>