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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 get_vertex_field_type(current_schema_type, vertex_field_name):
 """Return the type of the vertex within the specified vertex field name of the given type."""

    # According to the schema, the vertex field itself is of type GraphQLList, and this is
    # what get_field_type_from_schema returns. We care about what the type *inside* the list is,
    # i.e., the type on the other side of the edge (hence .of_type).
    # Validation guarantees that the field must exist in the schema.
    if not is_vertex_field_name(vertex_field_name):
        raise AssertionError(u'Trying to load the vertex field type of a non-vertex field: '
                             u'{} {}'.format(current_schema_type, vertex_field_name))

    raw_field_type = get_field_type_from_schema(current_schema_type, vertex_field_name)
    if not isinstance(strip_non_null_from_type(raw_field_type), GraphQLList):
        raise AssertionError(u'Found an edge whose schema type was not GraphQLList: '
                             u'{} {} {}'.format(current_schema_type, vertex_field_name,
                                                raw_field_type))
    return raw_field_type.of_type