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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_project_config_path(path=None):
 """Return project configuration folder if exist."""

    project_path = Path(path or '.').absolute().joinpath(RENKU_HOME)
    if project_path.exists() and project_path.is_dir():
        return str(project_path)