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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 generate_builder(self, entry_point, export_target):
 """ Yields exactly one builder if both the provided entry point and export target satisfies the checks required. """


        try:
            builder = entry_point.resolve()
        except ImportError:
            logger.error(
                "unable to import the target builder for the entry point "
                "'%s' from package '%s' to generate artifact '%s'",
                entry_point, entry_point.dist, export_target,
            )
            return

        if not self.verify_builder(builder):
            logger.error(
                "the builder referenced by the entry point '%s' "
                "from package '%s' has an incompatible signature",
                entry_point, entry_point.dist,
            )
            return

        # CLEANUP see deprecation notice below
        verifier = self.verify_export_target(export_target)
        if not verifier:
            logger.error(
                "the export target '%s' has been rejected", export_target)
            return

        toolchain, spec = self.extract_builder_result(builder(
            [entry_point.dist.project_name], export_target=export_target))
        if not toolchain:
            logger.error(
                "the builder referenced by the entry point '%s' "
                "from package '%s' failed to produce a valid "
                "toolchain",
                entry_point, entry_point.dist,
            )
            return

        if spec.get(EXPORT_TARGET) != export_target:
            logger.error(
                "the builder referenced by the entry point '%s' "
                "from package '%s' failed to produce a spec with the "
                "expected export_target",
                entry_point, entry_point.dist,
            )
            return

        if callable(verifier):
            warnings.warn(
                "%s:%s.verify_export_target returned a callable, which "
                "will no longer be passed to spec.advise by calmjs-4.0.0; "
                "please instead override 'setup_export_location' or "
                "'prepare_export_location' in that class" % (
                    self.__class__.__module__, self.__class__.__name__),
                DeprecationWarning
            )
            spec.advise(BEFORE_PREPARE, verifier, export_target)
        else:
            spec.advise(
                BEFORE_PREPARE,
                self.prepare_export_location, export_target)
        yield entry_point, toolchain, spec