#!/usr/bin/env python

from __future__ import print_function, absolute_import

import abc
import types
import numpy as np

class FitFunction(object):

    def __init__(self, python_function):

        assert isinstance(python_function, types.FunctionType)
        self._py_function = python_function

    @abc.abstractmethod
    def pretty_string(self):
        r"""
        Return some pretty string.
        """


class Gaussian(FitFunction):


    def __init__(self):

        def gaussian(x, mu, sigma, A):
            coeff = (_np.sqrt(2.0 * _np.pi) * sigma)**(-1.0)
            arg   = -.5 * (((x - mu) / sigma)**2.0)
            return A * coeff * _np.exp(arg)

        FitFunction.__init__(self, gaussian)

        @staticmethod
        def pretty_string():
            return "1D Gaussian"


if __name__ == "__main__":

    print("Gaussian.pretty_string: %s" % Gaussian().pretty_string)

me$ ./FitFunction_SO_test.py
Gaussian.pretty_string: <bound method Gaussian.pretty_string of <__main__.Gaussian object at 0x1005e2f90>>

me$ ./FitFunction_SO_test.py
Gaussian.pretty_string: "1D Gaussian"