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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 load_variables():
 """Load variables from environment variables."""

    if (not os.environ.get("PYCONFLUENCE_TOKEN") or
            not os.environ.get("PYCONFLUENCE_USER") or
            not os.environ.get("PYCONFLUENCE_ORG")):
        print ("One or more pyconfluence environment variables are not set. "
               "See README for directions on how to resolve this.")
        sys.exit("Error")

    global token
    global user
    global base_url
    token = os.environ["PYCONFLUENCE_TOKEN"]
    user = os.environ["PYCONFLUENCE_USER"]
    base_url = ("https://" + os.environ["PYCONFLUENCE_ORG"] + ".atlassian"
                ".net/wiki/rest/api/content")