Miscellaneous Functions

Utility functions for validating and formatting Brazilian tax identifiers (CNPJ) and international securities identifiers (ISIN). Functions marked vectorized operate element-wise on NumPy arrays.

from everysk.sdk.engines import Expression
expression_engine = Expression()

---

CNPJ

Brazilian companies are identified by a 14-digit CNPJ number. The functions below work with both the raw numeric string ('17210185000161') and the formatted mask ('17.210.185/0001-61').

is_valid_cnpj

is_valid_cnpj(value, check_dv=False)

Vectorized. Returns True if value is a structurally valid CNPJ. When check_dv=True, also validates the two check digits.

expression_engine.solve('is_valid_cnpj("17210185000161")', {})
# True

expression_engine.solve('is_valid_cnpj("00000000000000")', {})
# True  # structurally valid, even if not officially issued

expression_engine.solve('is_valid_cnpj("INVALID")', {})
# False

import numpy as np
expression_engine.solve('is_valid_cnpj(values)', {
    'values': np.array(['17210185000161', '12345678000195', 'INVALID', None])
})
# [True, True, False, False]

---

sanitize_cnpj

sanitize_cnpj(value, zfill=True)

Vectorized. Strips all non-numeric characters from value and returns the raw 14-digit string. When zfill=True (default), left-pads the result with zeros to ensure 14 digits.

expression_engine.solve('sanitize_cnpj("17.210.185/0001-61")')
# '17210185000161'

expression_engine.solve('sanitize_cnpj(17210185000161)')
# '17210185000161'

---

normalize_cnpj

normalize_cnpj(value, zfill=False, errors='raise')

Vectorized. Normalizes value to a canonical 14-digit CNPJ string. Unlike sanitize_cnpj, this function validates the result and raises or returns None on invalid input, depending on errors.

errors	Behavior on invalid input
'raise'	Raises an exception
'coerce'	Returns None

expression_engine.solve('normalize_cnpj("17.210.185/0001-61")')
# '17210185000161'

expression_engine.solve('normalize_cnpj("invalid", "coerce")')
# None

---

format_cnpj

format_cnpj(value, errors='raise')

Vectorized. Formats value as XX.XXX.XXX/XXXX-XX. On invalid input, raises or returns None depending on errors.

expression_engine.solve('format_cnpj("17210185000161")')
# '17.210.185/0001-61'

expression_engine.solve('format_cnpj("invalid", "coerce")')
# None

import numpy as np
expression_engine.solve('format_cnpj(values, "coerce")', {
    'values': np.array(['17210185000161', 'invalid'])
})
# ['17.210.185/0001-61', None]

---

generate_cnpj

generate_cnpj(valid_dv=False)

Generates a random 14-digit CNPJ string for testing. When valid_dv=True, the generated CNPJ will have correct check digits.

expression_engine.solve('generate_cnpj()')
# '48291037000158'  (example — output varies)

expression_engine.solve('generate_cnpj(True)')
# a 14-digit string that passes is_valid_cnpj with check_dv=True

---

ISIN

An ISIN (International Securities Identification Number) is a 12-character code: 2-letter country prefix, 9-character national identifier, and 1 check digit.

is_valid_isin

is_valid_isin(value, check_digit=True)

Vectorized. Returns True if value is a valid ISIN. When check_digit=True (default), also validates the check digit using the Luhn algorithm.

expression_engine.solve('is_valid_isin("US0378331005")')
# True  (Apple Inc.)

expression_engine.solve('is_valid_isin("BRPETRACNPR6")')
# True  (Petrobras PN)

expression_engine.solve('is_valid_isin("INVALID")')
# False

expression_engine.solve('is_valid_isin("US0378331004")')
# False  (wrong check digit)

expression_engine.solve('is_valid_isin("US0378331004", False)')
# True  (valid format, check digit skipped)

import numpy as np
expression_engine.solve('is_valid_isin(values)', {
    'values': np.array(['US0378331005', 'BRPETRACNPR6', 'INVALID', None])
})
# [True, True, False, False]