functools_partial.py

# Modified version of PowerMeta from
# http://www.pydanny.com/python-partials-are-fun.html

from functools import partial


def power(base, exponent):
    return base ** exponent


class Power(object):

    def __init__(self):

        # generate 50 partial power functions:
        for x in range(1, 51):

            # Set the partials to the class
            setattr(
                # cls represents the class
                Power,

                # name the partial
                "p{}".format(x),

                # partials created here
                partial(power, exponent=x)
            )
        # super(Power, cls).__init__(name, bases, dct)

p = Power()
print("\nUsing instances")
for i in range(1, 4):
    print("%d^2: %d" % (i, p.p2(i)))
# Prints:
# Using instances
# 1^2: 1
# 2^2: 4
# 3^2: 9

print("\nUsing class (no instantiation)")
for i in range(1, 4):
    print("%d^2: %d" % (i, Power.p2(i)))

# Prints:
# Using class (no instantiation)
# 1^2: 1
# 2^2: 4
# 3^2: 9