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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_input(self):

 		"""Returns form input field of Field.
 		"""

		name = self.attrs.get("_override", self.widget.__class__.__name__)
		self.values["field"] = str(FIELDS.get(name, FIELDS.get(None))(self.field, self.attrs))