In GraphQL, scalar coercion is the process of converting a value from one type to another, as it flows through the resolvers. This is needed when the input value for a field does not match the expected type, but can still be successfully converted to the correct type.
Scalar coercion can be implemented in the resolvers by using the GraphQLScalarType constructor to define a custom scalar type and providing a coerce function that can convert the input value to the correct type.
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