@classmethod
def checkRequiredInputFields(cls, dframe, requiredFields):
    """
        Checks that dframe has the fields in the array requiredFields. Also checks that there are
        no duplicate fields Returns True on success. Raises a ValueError on failure.
        :params dframe: The DataFrame that is being checked.
        :paras requiredFields: The fields that are required.
        """
    actualFields = dframe.columns
    if len(actualFields) != len(set(actualFields)):
        err = 'Your DataFrame has duplicate columns'
        raise ValueError(err)
    if set(requiredFields) <= set(actualFields):
        return True
    else:
        err = (
            '\n\nYour DataFrame is missing some required fields ... Including:\n     '
            )
        err += str(set(requiredFields) - set(actualFields))
        if 'Date' in str(set(requiredFields) - set(actualFields)):
            err += (
                '\nNote that DAS exports lack a Date field and it must be supplied. \n'
                )
        raise ValueError(err)
