code: def assertStartsWith(self, expectedPrefix, text, msg=None):
      if not text.startswith(expectedPrefix):
          if len(expectedPrefix) + 5 < len(text):
              text = text[: len(expectedPrefix) + 5] + "..."
          standardMsg = "{} not found at the start of {}".format(
              repr(expectedPrefix), repr(text)
          )
          self.fail(self._formatMessage(msg, standardMsg))
  
imports: import unittest
  import markdown
label_desc: Use image node_id 1 for calling the TestCaseWithAssertStartsWith obj's underlying member method code with example usage: obj.assertStartsWith(expectedPrefix, text, msg) without return types