Example of Software Design Pattern's Template Method.

Design_Patterns_Template_Method.py

class ProjectFile:
    safe_save = 0

    def __init__(self, file_name):
        self.file_name = file_name

    def save(self):
        print("{", self.file_name, "} Saving ...")

    def safe_save(self):
        if (self.validate()):
            self.reformat()
            self.save()
        else:
            print("{", self.file_name, "} Not saved")

class RubyFile(ProjectFile):
    def validate(self):
        print("[RubyFile] Validate")
        return True

    def reformat(self):
        print("[RubyFile] Reformatting")

class XmlFile(ProjectFile):
    def validate(self):
        print("[XmlFile] Validate")
        return True

    def reformat(self):
        print("[XmlFile] Reformatting")

class PdfFile(ProjectFile):
    def validate(self):
        print("[PdfFile] Skip Validate")
        return False

    def reformat(self):
        print("[PdfFile] Reformatting")

ruby_file = RubyFile("bar.rb")
xml_file = XmlFile("foo.xml")
pdf_file = PdfFile("wise.pdf")

xml_file.safe_save()
pdf_file.safe_save()
ruby_file.safe_save()