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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 get_marshaller_for_type_string(self, type_string):
 """ Gets the appropriate marshaller for a type string. Retrieves the marshaller, if any, that can be used to read/write a Python object with the given type string. The modules it requires, if available, will be loaded. Parameters type_string : str Type string for a Python object. Returns ------- marshaller : marshaller or None The marshaller that can read/write the type to file. ``None`` if no appropriate marshaller is found. has_required_modules : bool Whether the required modules for reading the type are present or not. See Also -------- hdf5storage.Marshallers.TypeMarshaller.python_type_strings """

        if type_string in self._type_strings:
            index = self._type_strings[type_string]
            m = self._marshallers[index]
            if self._imported_required_modules[index]:
                return m, True
            if not self._has_required_modules[index]:
                return m, False
            success = self._import_marshaller_modules(m)
            self._has_required_modules[index] = success
            self._imported_required_modules[index] = success
            return m, success
        else:
            return None, False