sys.modules is a dictionary that contains all loaded modules’ names as keys.

Anonymous functions are declared with lambda instead of def.
Lambda definitions are expressions and may therefore not contain if-statements and the like.
map(foo, list1, list2, list3) is like [foo(*tuple) for tuple in zip(list1, list2, list3)].
By using yield instead of return to provide a return value, you create a function that returns a generator object that returns one [...]

Perl
Python

my $x = 10;
sub foo
{
$x = 20;
}

x = 10
def foo():
global x
x = 20

Declaring a variable in a function as global is only necessary for reassignments, not for mere read-access.
def foo(x, y, z): pass
foo(10, 20, 30)
does the same as
[...]

A function definition may be put inside an if-block.
if DEBUG:
  def do_something():
    print ‘useful debug information’
    do_some_work()
else:
  def do_something():
    do_some_work()

Docstrings are available at runtime via the __doc__ attribute.
The reference count of any object is available via sys.getrefcount(object).

while and for loops may have an else block that is executed if the loop terminates naturally, that is, not by a break statement.
There is a no-op statement called pass.
Assignments to variables do not return the assigned value; they are statements, not expressions.
You can build your own iterables by implementing a next method that raises [...]

There is no switch statement.
Boolean AND, OR and NOT are really just and, or and not, there’s neither && nor || nor ! in Python.

Because Python doesn’t guess default values, a sequence assignment like fst, snd = some_sequence works iff some_sequence has length 2.
There is no auto-increment and no auto-decrement.
Names beginning with single or double underscore have special meaning.
Names of built-ins can be reassigned.
Combined comparisons for range checks: x < y <= z.

The Wisdom of Crowds:
The Wisdom of Crowds: Why the Many Are Smarter Than the Few and How Collective Wisdom Shapes Business, Economies, Societies and Nations, first published in 2004, is a book written by James Surowiecki about the aggregation of information in groups, resulting in decisions that, he argues, are often better than could have [...]

elsif is called elif.
Parens around boolean tests are optional.
A semicolon can be put at the end of any statement to make it look like C.
Parts of statements enclosed in parens, curlies or brackets may span over multiple lines.
Since parens may be wrapped around each expression, virtually anything can be spread over [...]