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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 convert_coerce_type_and_add_to_where_block(coerce_type_block, where_block):
 """Create an "INSTANCEOF" Filter from a CoerceType, adding to an existing Filter if any."""

    instanceof_filter = convert_coerce_type_to_instanceof_filter(coerce_type_block)

    if where_block:
        # There was already a Filter block -- we'll merge the two predicates together.
        return Filter(BinaryComposition(u'&&', instanceof_filter.predicate, where_block.predicate))
    else:
        return instanceof_filter