You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by 2,3,6,9,10-pentachloro-5-(2,3-dichlorobuta-1,3-dienyl)-7-methylideneundeca-1,3,5,8,10-pentaene ?
user
C16H11Cl7
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