def test_address__normalize_phone_number__6():
"""`normalize_phone_number` replaces leading '00' by plus sign.
The country code is ignored in this case.
"""
assert '+421234567891' == normalize_phone_number('0042-1234/5678-91',
'+49')
def test_address__normalize_phone_number__7():
"""`normalize_phone_number` replaces only leading '00' by plus sign."""
assert '+421234007891' == normalize_phone_number('0042-1234/0078-91',
'+49')
def test_address__normalize_phone_number__5():
"""`normalize_phone_number` does not replace '0' on empty country code."""
assert '01234567891' == normalize_phone_number('01234/5678-91', '')
def test_address__normalize_phone_number__4():
"""`normalize_phone_number` replaces only the first '0' by country code."""
assert '+491234507090' == normalize_phone_number('01234/5070-90', '+49')
def test_address__normalize_phone_number__3():
"""`normalize_phone_number` replaces a leading '0' by the country code."""
assert '+491234567891' == normalize_phone_number('01234/5678-91', '+49')
def test_address__normalize_phone_number__2():
"""`normalize_phone_number` keeps only numbers and a leading plus sign."""
assert '+491234567890' == normalize_phone_number('+49 (1234) 5678 - 90X',
'+49')
def test_address__normalize_phone_number__1():
"""`normalize_phone_number` returns a normalized number unchanged."""
assert '+491234567890' == normalize_phone_number('+491234567890', '+49')