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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 is_commutable(expr1, expr2, eps=0.00000001):
 """Test whether expr1 and expr2 are commutable. Args: expr1 (Expr, Term or Pauli operator):
 Pauli's expression. expr2 (Expr, Term or Pauli operator):
 Pauli's expression. eps (float, optional):
 Machine epsilon. If |[expr1, expr2]| < eps, consider it is commutable. Returns: bool: if expr1 and expr2 are commutable, returns True, otherwise False. """

    return sum((x * x.conjugate()).real for x in commutator(expr1, expr2).coeffs()) < eps