Python Restrictions

Native Python objects are implicitly typed. This means that the following instructions are valid since the assigned rhs has a static type.

x = 1                   # OK
y = 1.                  # OK
s = 'hello'             # OK
z = [1, 4, 9]           # OK
t = (1., 4., 9., 16.0)  # OK

Concerning lists and tuples, all their elements must be of the same type.

z = [1, 4, 'a']         # KO
t = (1., 4., 9., [])    # KO