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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 _set_doc(self, func):
 		""" 		If no doc was explicitly set, use the function's docstring, trimming 		whitespace and replacing newlines with spaces. 		"""

		if not self.doc and func.__doc__:
			self.doc = func.__doc__.strip().replace('\n', ' ')