def __init__(self, package, version):
        """Construct a new requirement.

        :param package: the package name.
        :param version: a semver compatible version specification.
        """
        self.package = package
        self.version = version
        if self.version and not re.match(r"[<=>~]", version[:2]):
            self.version = "=={}".format(self.version)
def circle(self,x,y,r):
		for x_offset in range(-r,r+1):
			for y_offset in range(-r,r+1):
				if sqrt(x_offset**2+y_offset**2)<r:
					self.board[x+x_offset,y+y_offset] = self.color