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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 check_required(config):
 """Validate the input"""

    if config.get('domain_key') is None:
        raise CfgError("The domain_key option is required")
    if config.get('remote_loc') is None:
        raise CfgError("The remote_location option is required")
    if config.get('gpg_keyid') is None:
        raise CfgError("The gpg_keyid option is required")