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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 program_unit_name(line:str) -> str: """Given a line that starts a program unit, i.e., a program, module, subprogram, or function, this function returns the name associated with that program unit."""

   match = RE_PGM_UNIT_START.match(line)
   assert match != None
   return match.group(2)