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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 _open(self, file_path=None):
 		""" 		Opens the file specified by the given path. Raises ValueError if there 		is a problem with opening or reading the file. 		"""

		if file_path is None:
			file_path = self.file_path

		if not os.path.exists(file_path):
			raise ValueError('Could not find file: {}'.format(file_path))

		try:
			f = open(file_path, encoding='utf-8', newline='')
		except OSError as err:
			self.log.error(str(err))
			raise ValueError('Could not open file: {}'.format(file_path))

		return f