@pimms.require<EOL><INDENT>def validate_vertex_properties_size(_properties, vertex_count):<DEDENT>
if   _properties is None: return True<EOL>elif _properties.row_count == <NUM_LIT:0>: return True<EOL>elif _properties.row_count == vertex_count: return True<EOL>else:<EOL><INDENT>s = (_properties.row_count, vertex_count)<EOL>s = '<STR_LIT>' % s<EOL>raise ValueError(s)<EOL><DEDENT>
validate_vertex_properties_size requires that _properties have the same number of rows as
the vertex_count (unless _properties is empty).