PyCon2011_AdvancedPythonIOptimizations.py

def one_third(x):
    return x / 3.0

def make_table(pairs):
    'Unoptimized Example'
    result = []
    for value in pairs:
        x = one_third(value)
        result.append(format(value, '9.5f'))
    return '\n'.join(result)


def make_table2(pairs):
    'Optimized version'
    result = []
    result_append = result.append   # bound method
    _format = format                # localized
    for value in pairs:
        x = value / 3.0             # in-lined
        result_append(_format(value, '9.5f'))
    return '\n'.join(result)