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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 cos_c(self, N=None):
 # percent=0.9, 		"""Return the squared cosines for each column."""


		if not hasattr(self, 'G') or self.G.shape[1] < self.rank:
			self.fs_c(N=self.rank)  # generate
		self.dc = norm(self.G, axis=1)**2
		# cheaper than diag(self.G.dot(self.G.T))?

		return apply_along_axis(lambda _: _/self.dc, 0, self.G[:, :N]**2)