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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def find_tabs(self, custom_table_classes=None):
 """Finds all classes that are subcalss of Table and loads them into a dictionary named tables."""

        for module_name in get_all_modules(self.package_path):
            for name, _type in get_all_classes(module_name):
                # pylint: disable=W0640
                subclasses = [Table] + (custom_table_classes or list())
                iss_subclass = map(lambda c: issubclass(_type, c), subclasses)
                if isclass(_type) and any(iss_subclass):
                    self.tabs.update([[name, _type]])