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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_requirements(self):
 """Generate the info to create requirements.txt in the toookit."""

        if not self._pip_packages:
            return

        reqs = ''
        for req in self._pip_packages:
                reqs += "{}\n".format(req)
        reqs_include = {
            'contents': reqs,
            'target':'opt/python/streams',
            'name': 'requirements.txt'}

        if 'opt' not in self._files:
             self._files['opt'] = [reqs_include]
        else:
             self._files['opt'].append(reqs_include)