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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 find_descriptor_schemas(self, schema_file):
 """Find descriptor schemas in given path."""

        if not schema_file.lower().endswith(('.yml', '.yaml')):
            return []

        with open(schema_file) as fn:
            schemas = yaml.load(fn, Loader=yaml.FullLoader)
        if not schemas:
            self.stderr.write("Could not read YAML file {}".format(schema_file))
            return []

        descriptor_schemas = []
        for schema in schemas:
            if 'schema' not in schema:
                continue

            descriptor_schemas.append(schema)

        return descriptor_schemas