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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 add_dependencies(self, module):
 """ Adds a module and its dependencies to the list of dependencies. Top-level entry point for adding a module and its dependecies. """


        if module in self._processed_modules:
            return None

        if hasattr(module, "__name__"):
            mn = module.__name__
        else:
            mn = '<unknown>'

        _debug.debug("add_dependencies:module=%s", module)

        # If the module in which the class/function is defined is __main__, don't add it. Just add its dependencies.
        if mn == "__main__":
            self._processed_modules.add(module)

        # add the module as a dependency
        elif not self._add_dependency(module, mn):
            _debug.debug("add_dependencies:not added:module=%s", mn)
            return None

        _debug.debug("add_dependencies:ADDED:module=%s", mn)

        # recursively get the module's imports and add those as dependencies
        for dm in self._find_dependent_modules(module):
            _debug.debug("add_dependencies:adding dependent module %s for %s", dm, mn)
            self.add_dependencies(dm)