urandom: Update docstring style.

Also remove the tip boxes. The entire documentation consist of tips of
one form or another.

Boxes should only be used when necessary such as safety reasons (warnings)
or to prevent costly/time consuming mistakes (notes/tips).

src/urandom/__init__.py

@@ -8,6 +8,9 @@
 
 """
 This module implements pseudo-random number generators.
+
+All functions in this module should be used with positional arguments. Keyword
+arguments are not supported.
 """
 
 from typing import Any, Optional, Sequence, overload
@@ -15,19 +18,18 @@ from typing import Any, Optional, Sequence, overload
 
 def seed(a: Optional[int] = None) -> None:
     """
-    Initialize the random number generator.
+    seed(value=None)
 
-    Args:
-        a: Optional seed value. If ``None``, the system timer will be used.
+    Initializes the random number generator.
 
-    .. tip:: This is called when the module is imported, so normally you do
-        not need to call this.
+    This gets called when the module is imported, so normally you do
+    not need to call this.
+
+    Arguments:
+        value: Seed value. When using ``None``, the system timer will be used.
     """
 
 
-# integers
-
-
 @overload
 def randrange(stop: int) -> int:
     ...
@@ -45,7 +47,25 @@ def randrange(start: int, stop: int, step: int) -> int:
 
 def randrange(start, stop, step):
     """
+    randrange(stop) -> int
+    randrange(start, stop) -> int
+    randrange(start, stop, step) -> int
+
     Returns a randomly selected element from ``range(start, stop, step)``.
+
+    For example, ``randrange(1, 7, 2)`` returns random numbers from ``1`` up to
+    (but excluding) ``7``, in increments of ``2``. In other words, it
+    returns ``1``, ``3``, or ``5``.
+
+
+    Arguments:
+        start (int): Lowest value. Defaults to ``0`` if only one argument is given.
+        stop (int): Highest value. This value is *not* included in the range.
+        step (int): Increment between values. Defaults to ``1`` if only one
+            or two arguments are given.
+
+    Returns:
+        The random number.
     """
 
 
@@ -77,13 +97,12 @@ def choice(seq: Sequence[Any]) -> Any:
 
 def random() -> float:
     """
-    Return the next random floating point number in the range [0.0, 1.0).
+    random() -> float
 
-    .. tip:: The `interval notation`_ indicates that this includes 0.0 and
-        excludes 1.0.
+    Gets a random value between ``0`` and ``1``.
 
-    .. _interval notation:
-        https://en.wikipedia.org/wiki/Interval_(mathematics)#Notations_for_intervals
+    Returns:
+        A random value satisfying :math:`0 \\leq x < 1`.
     """