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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_inputs(compulsory_fields, fields):
 """Helper function to check if the layer has every compulsory fields. :param compulsory_fields: List of compulsory fields. :type compulsory_fields: list :param fields: inasafe_field dictionary from the layer. :type fields: dict :raises: InvalidKeywordsForProcessingAlgorithm if the layer is not valid. """

    for field in compulsory_fields:
        # noinspection PyTypeChecker
        if not fields.get(field['key']):
            # noinspection PyTypeChecker
            msg = '%s not found in %s' % (field['key'], fields)
            raise InvalidKeywordsForProcessingAlgorithm(msg)