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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 fetch_string(self, context, name):
 """ Get a value from the given context as a basestring instance. """

        val = self.resolve_context(context, name)

        if callable(val):
            # Return because _render_value() is already a string.
            return self._render_value(val(), context)

        if not is_string(val):
            return self.to_str(val)

        return val