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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_fc_date(out_config_file):
 """Retrieve flowcell date, reusing older dates if refreshing a present workflow. """

    if os.path.exists(out_config_file):
        with open(out_config_file) as in_handle:
            old_config = yaml.safe_load(in_handle)
            fc_date = old_config["fc_date"]
    else:
        fc_date = datetime.datetime.now().strftime("%y%m%d")
    return fc_date