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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_pex_python_paths():
 """Returns a list of paths to Python interpreters as defined in a pexrc file. These are provided by a PEX_PYTHON_PATH in either of '/etc/pexrc', '~/.pexrc'. PEX_PYTHON_PATH defines a colon-separated list of paths to interpreters that a pex can be built and run against. """

    ppp = Variables.from_rc().get('PEX_PYTHON_PATH')
    if ppp:
      return ppp.split(os.pathsep)
    else:
      return []