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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 create_project(self, name=None, project_id=None, path=None):
 """ Create a project and keep a references to it in project manager. See documentation of Project for arguments """


        if project_id is not None and project_id in self._projects:
            return self._projects[project_id]
        project = Project(name=name, project_id=project_id, path=path)
        self._check_available_disk_space(project)
        self._projects[project.id] = project
        return project